The Steam Machine is slightly bigger than a portable Blu-ray / DVD player. (I just checked this with my own players)
I can’t wait for someone to make the equivalent of the Gamecube’s GBA Player for discs. Because of its size, It could even be a plastic shell where you put an existing Hitachi/LG portable drive without having to disassemble anything
the game boy player? absolutely. it was basically a full gba, too. you needed a driver disk for the gamecube to find it, but after that the console just idled and handled io passthrough while the peripheral did all the work.
not like those sega hacks who shipped an entire copy of windows for mips just to play their weird shmups.