Currently the Steam Deck. Between having (most of) my whole Steam Library availble, being able to run EGS/GOG via Heroic Launcher and all the emulators available, it's like having my entire gamining history all in one machine.
Plus in Desktop Mode it's pretty much a full-on desktop Linux PC as well.
I love that emulation lets me play small screen games on a big screen (I know the Steam Deck can do both, but the pitch is more 'big screen games made portable')