A few years ago I encountered a rather amusing short science fiction story entitled "They're Made Out of Meat" by Terry Bisson. I carried it around on my Palm for a long time, and it surfaces as a meme every once in a while. (I won't spoil it for you by summarizing here. It's pretty short so you can read it yourself.)
This story has now been made into a live action short film Grand Prize at the Science Fiction Museum's SF Short Film Festival in Seattle.