Technologies created by (evil) hackers
HomeySan: I'm thinking l0phtcrack.The original SATAN scanner from Dan Farmer; the concept, though. Bad guys had a bag of tricks that they'd use to get in. He compiled a list and built an automated tester of those tricks.Some of the concepts that evil hax0rz/crackers used to obfuscate code in viruses have migrated into the mainstream as a method of protecting intellectual property.