100 Most Evil People Ever Experiment

I need your help. I'm conducting an experiment. In order to maintain the validity of this experiment, I cannot reveal my hypothesis at this time. But part of the experiment is to assemble a list of the 100 most evil people ever. These can be both real and/or fictional beings.

Would you like to help?

If so (and I hope you will), simply send me your suggestions for the list. Send one name or ten names or 100 names. Every contribution will help. Post the names in the comment section of this post or send me an email or tweet the names of evil people with the hashtag #100EvilPeople.

If you could share this with your friends, that would help, too. As with most experiments, the more data I gather, the better. 

Once the list is complete, I will share it here and reveal the purpose for its creation.