Gamespy has a pretty good article on the dumbest moments in gaming histroy. It's in several parts, so 11-15 will be released tomorrow.
The best one so far, IMO, is the MCA vs. Nintendo one. Not only was it moronic, it was Darwin-Award winnign stupid. Have fun MCA, err, MCA Universal, err, Vivendi-Universal.
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You know, a link would be nice:
http://www.gamespy.com/articles/june...ts/index.shtml