Well, it wasn't technically a dare, but I did jump off my friends roof last October. It was for this game called regnevacs. Think scavenger hunt meets jackass. It's awesome. Some other crazy things our team did:
-Went to a gas station and bought gum with a ski mask on.
-Drank 4 redbulls in less than 2 minutes while in underwear and getting shot by a paintball gun from about 10 ft. (Thank god I didn't do that one...)
-Duck taped someone to a pole and had him take a shit while taped on. This one was actually really funny, because we taped him to a light pole in a park, and as he was getting ready to shit, a wedding came in a bus for pictures. And they all walked right past him, and completely ignored him.
There's a bunch more, but those are highlights.