I ported Doom to Dreamcast by using doomgeneric, it was extremely easy. :)
The game is rendered to the texture and then this texture is used for an in-game OS (which mimics Windows 95 for now), which in turns get rendered to yet another texture in 3D world to simulate the screen. Dreamcast's keyboard is supported as an input source.
The cat got a PC now!
It's not just an image, you can use Dreamcast Mouse and keyboard to interact with a fake Windows 95 recreation (see [the video](https://www.youtube.com/watch?v=IQLwQ98EN68)).
I want to make my own small fake OS you can play around with, maybe even do Internet and SD card support. It would be cool to add a PICO8-like "Dream console" API so that you could write games for in-game PC. :)