Riff-Raff: This sexy stud is Dr. Frank's beguiling buttler. Do you fancy yourself the servile, sadistic alien type? Or maybe you've always wanted long flowing blond hair and a humpback. Either way, I have a totally disgusting crush on anyone who dresses up like Riff-Raff.
American McGee's Alice and Johnny the Homicidal Maniac: This one's a twofer, only because I love this picture. In my mind I'm planning the Alice and Nny wedding ceremony. Pretty sure all the guests will be bloodily slaughtered.
Bender from Futurama: Yes, you need the booze! And yes, I've mostly included Bender because it amuses me that someone would tolerate wearing this costume for even a moment. You, sir or ma'am, have balls.
Need I say more? Crossdressers are the highlight of my halloween experience.