Technologies created by (evil) hackers
dugsong: I'm guessing you mean non-security technologies? How about consumer P2P?See Joseph Menn's book on Napster for the backstory behind MP3 file sharing (many of us w00w00 folks were involved, including guys like "minus", who stole the Winamp source code off my friend Ian Rogers' laptop).Other example I can think of - anakata and The Pirate Bay, which is sort of mainstream, I guess (!)