I remember reading about this back in the day: A remake of the original Resident Evil developed for the GameBoy Color.
Unfortunately the game never saw the light of day--though I guess I can understand why Capcom (or whoever produced the game) would be a bit wary of trying to sell a highly pixelated version of a game known for graphics that scare the hell out of people.
A few videos of the game--along with a brief video of Resident Evil for the GameBoy Advance--have popped up on YouTube and are quite interesting. I know I should be more impressed with the polygons appearing in the RE2 video, but to be perfectly honest it's the RE1 video that interested me the most. That's probably because instead of seeing a pixelated mess, I see an almost impressionist take on the game that started the entire survival horror genre of games.
Now where's the ROM of this thing so we can try it out for ourselves?