What's your "Oh fuck, that actually worked!" Linux moment that made you feel like a wizard?

exiting out of vim

That this worked when I did it in 2006:

wine ~/.wine/drive_c/Program\ Files/Warcraft\ III/Frozen\ Throne.exe -opengl

Wine still feels like magic in 2025
Yes! It used to be so hit or miss with Wine, but I played WoW in it around the same time and it was crazy that it worked (at least most of the time).
Yet in 2025 w3c is a pain in the ass

When I actually get an awk/sed command to work.

I've had the 1980's awk book seemingly "forever", but use awk so infrequently I always need to look things up.

In the early 2ks, computer were ugly grey box with noisy fan and a hard drive that gave the impression a cockroach colony were trying to escape your case. I wanted to build a silent computer to watch Divx movies from my bed, but as a broke teen, I just had access to disposed hardwares I could find there and there.

I dismantled a power supply, stuck mosfets to big mother fucking dissipator, and I had a silent power supply. I put another huge industrial dissipator on CPU (think it was an AMD k6 500Mhz) and had fanless cooling. Remained the hard drive.

Live CD/USB weren't common at that time. I've discovered a live CD distrib (I think it was Knoppix) that could run entirely from RAM.

I removed hard drive, boot on live distrib, then replace CD by my Divx and voila.

Having a fanless-harddriveless computer was pure science fiction for me and my friends at that time.

computer were ugly grey box with noisy fan and a hard drive that gave the impression a cockroach colony were trying to escape your case.

I miss it so much

Moving from old to new Laptop by piping /dev/sda3's content through netcat and into /dev/nvme0n1p3

Using dd to move-resize a partition by writing down the cylinder numbers and moving it piece by piece like some Tower of Hanoi. Wanted to add more space to my root after deleting the Windows partition, which happened to be first. There is apparently no built-in command to do that.

Booted up fingers crossed and everything worked.
- I always liveboot debian and just use Gparted, faster than figuring out the commands manually, and much less risky
How did you do it? Did you run a live distro on the new laptop to receive and overwrite the SSD ?
- Livebooted (Arch) on both, I think you can even remove the install media after it copied itself to RAM, though I'm not sure (especially with Ventoy in between).

Piped the ps2 usb camera /dev/video0 to nc. Reverse port fwd'd to my router 200 miles away, and got vlc 200 miles to connect to that port and it worked. No rtsp or server required

And now we have a new streaming service 🤔 Really nice.

I was thinking that by now, we should have enough bandwidth to stream webcams straight to each other without HLS or WebRTP or whatever. Just make the device available over a port or, as you did, cat it to another PC and voilà. Actually, why don't we stream raw camera feeds?

Anti Commercial-AI license
- Most devices will give you the latest frame on a read essentially. VLC accepts a tcp:// address and interpreted it correctly somehow. The raw bandwidth on the potato 320x240 or whatever was peanuts, but even if you didn't get all the frames per second the device will discard old frames and you got the latest frame anyway. So pretty cool indeed. Doesn't really multicast though. For that I suppose you could netcat to local multicast address and then connected to that same address, but I've never tried it. VLC may not receive the headers that a read may open with would be my suspicion

scp

I'm never using a flash drive again.

especially nice when you get path completion on the target server :D
- Note: to do this you have to have your public key on the remote server
Next step: rsync, because it lets you resume.

When the network printer suddenly started printing the picture my kid had drawn in tux paint without me having configured the printer on their PC.

You might actually be a wizard lmao
- The real wizards are the folks who made KDE's printer integration. Or maybe CUPS.

I made a custom Linux image to run inside a web browser. No particular distro, just a Linux kernel (compiled with a custom configuration to produce a tiny binary), a shell, and a few small apps.

When reading from the filesystem, it made HTTP requests for each file (+ browser caching), so no need to load a disk image all at once. IIRC, I got the cold boot time down to <1 second (after assets were already cached from a previous load though).

I also got NixOS to run in the browser, but even after stripping out as much as possible, it was still really slow due to systemd. (I'm not a systemd hater, resources are just very limited when running this way.)

I used an x86 emulator called v86. It's a very cool project 🙂

Honestly, im suprised everytime I blindly follow an online tutorial, copying and pasting like a madman, and my hard drive isn't wiped.

I used the aircrack-ng tools to capture wep packets and decrypt my neighbors WiFi because I was broke and needed internet to study back in college..I was a total noob (still am) and when I saw the password in the terminal I felt like I was a total hackerman. It was great!

Not quite as impressive, but I somehow fucked up something with my bootloader lately and couldn't boot anymore into my main drive. Loaded up a live usb stick and made a new ESP partition, arch-chroot and grub-install/grub-makecfg and it worked again.

Yes, I just followed a guide, but I am still fascinated this just worked on the first try.

NixOS in a VM for a few weeks and made it how I liked, copied that VM to server to VNC in (laptop battery was suffering), kept customising until i had it nice.... and then when it came to wipe my laptop for the nixos setup, I was bit scared.

But low and behold, nixos-build switch and then it was all there, just like the VM. Fucking amazing.

Ubuntu like 10 years ago, drop to terminal (Ctrl+Alt+F5 or something), vlc video.mp4 Aand it started playing it with ASCII graphics. Magic

Recovered a legacy COBOL 911 dispatch system after the hard drive containing the root filesystem died, which wasn't RAID protected at all and had no complete backups except for a few days prior when I started running daily rsync backups out of paranoia because the idiot dipshit sysadmin who set it all up left the company to work directly for one of our customers.

Thankfully the data volume was RAID protected and didn't die so the critical data was pretty much all there ready to go again after some rebuilding of shit.

Still, took 15 hours to recover. Was a RHEL 4 system when RHEL 6 was current, and we had no way of obtaining the install media or licensing, so I dug up an archived CentOS 4 iso and installed from that, and got stuff working mostly just by copying various files from backup.

Fucking nightmare come true. Drive crashed at noon and we didn't go home until about 4am.

The first time I learned about PDFGrep, I was able to track down a purchase order that would have taken hours otherwise.

Maybe a little specific, but the first time i used autorandr, I was wow it does exactly what it sounds like it does.

Oh! I just thought of a better one. The first time you run vim scp://user@server//home/user/.

Once upon a time I was installing Linux on a tiny little laptop, whose brand name I've forgotten. It was probably a Lenovo. Anyway, it was extremely difficult to install anything on it, and they went to great lengths to make sure no one would be able to install Linux on it. I spent an entire day messing around with the grub terminal, and began to suspect that it had a built-in cut off for the USB port during boot. I think I saw some log output to that effect, but I couldn't find any way to disable it. After some thought, I got back in grub, unplugged the USB stick that I was installing Linux from, and plugged it back in. The laptop detected and mounted the external drive and I tried to install again.

Worked perfectly.

Oh so many fun adventures, too much to count... But a few nice ones:

HDD died, so ran a desktop system over network from a NAS (nfs) without HDD.. for months.
Rebuilding a corrupted system (any bit advanced tools wouldn't start anymore, like apt).
Custom bootable live cd based on Linux From Scratch (around 2002).
Anything related to Kerberos and NFS4.
Replacing syscalls to run software from a ramdrive that would otherwise not work.
Recently using debootstrap to install Kubuntu with a ZFS root, which went surprisingly smooth and pretty easy.

I love Linux for all these insane possibilities.

Installing Linux on the Nintendo DS (https://www.dslinux.org/) was pretty impressive for me.

I used to be a build engineer at an enterprise Linux company that built custom Linux distributions for various device manufacturers.

I built a whole build automation system that used what would be the equivalent of a Docker container for the build system, and it was distributed across the whole company to make simultaneous build in parallel and a system that would check how many build systems were in use or available with a queueing system.

All written in Bash, Perl and Python.

When the whole shebang of piping/redirection landed, thinking of all the possibilities!

Migrated a server to a new drive by copying all the files with rsync and chrooting into it. Nothing too impressive from a linux standpoint, but I had no idea that was possible until I tried it.

I used to do this to migrate user profiles on Macs at my previous employer. I'd ssh in and copy everything across the network and then have the user log in on the other computer like magic. Network copy is a beautiful thing.

2 that stand out to me:

When I successfully got virtualbox to boot my windows xp partition inside Linux because I needed to run some software for school.

When I figured out how to use qemu-nbd to mount a qcow2 image backed by a physical block device in order to run non-destructive filesystem repair and file recovery with test disk. Did that for a while for my university IT help desk to quickly save files off failing disks.

If you have binary that is hardcoded to look for some files/libs in a certain path, you can overwrite that path with sed directly lol. You just need to make sure to keep the string length the same.

sed -i s|/usr|././|g will change /usr for the current working dir for example.

Would you believe me if I told you this is how conda works? :P

Disabling CPUs by writing a zero to some file under /sys

mdadm

I tripped over a cord once and broke the screen on my laptop. I salvaged the disk for another purpuse. But I got some prime hardware here, it's got video output, it's got ram, and a cpu! I used it for my lectures; liveusb with some persistent storage on, put my slides on there and fire it up. Did not have to unplug the normal laptop from my office. Nothing magic really, but some students were puzzled.

Probably installing a different kernel and adding it to systemd boot manually a while back.

Oh and the very first was most likely installing Arch manually.

Random one recently:

Turned my gaming box into an impromptu audio mixer by connecting my PS5 audio into the line in and routing it with pipewire to the speaker output so I could game while watching endurance racing on the same speakers.

Later found it was easier to do visually with qpwgraph.