Dhruin
SasqWatch
"Demakes" are new to me but Bethsoft has put one together to market Fallout 3 for the Japanese market. For those interested, you can download a "game" that looks like an 8-bit RPG with Fallout 3 references - you'll need to understand Japanese or just be interesting in futzing around. Full story at the Bethblog (thanks to Omega for a similar story).
More information.
More information.