This is actually an old post on the Net, but it's new to me. This is the top 100 things Evil Overlords should learn from movies. Thanks to Grow a Brain. Here's a sample:

2. My ventilation ducts will be too small to crawl through.

8. After I kidnap the beautiful princess, we will be married immediately in a quiet civil ceremony, not a lavish spectacle in three weeks' time during which the final phase of my plan will be carried out.

12. One of my advisors will be an average five-year-old child. Any flaws in my plan that he is able to spot will be corrected before implementation.

32. I will not fly into a rage and kill a messenger who brings me bad news just to illustrate how evil I really am. Good messengers are hard to come by.

70. When my guards split up to search for intruders, they will always travel in groups of at least two. They will be trained so that if one of them disappears mysteriously while on patrol, the other will immediately initiate an alert and call for backup, instead of quizzically peering around a corner.

85. I will not use any plan in which the final step is horribly complicated, e.g. "Align the 12 Stones of Power on the sacred altar then activate the medallion at the moment of total eclipse." Instead it will be more along the lines of "Push the button."