if sell it for less than or equal to $100 bucks, i rather keep it for:
1. give it to my one of my relatives, or
2. give it to my daughters (they could have fun with it), or
3. keep it for experiment purpose, or
4. use it in creating textures, etc
note: my 7-year-old daughter and i am still using my 30d since one of the local camera store offers me for $250. it still serves me well though...