Here are some robot costumes you may want to make, if you've got enough time (and in this economy, you may, involuntarily):
Image source: www.teamdroid.com
Image source link
Here are the links to learn how to make them:
Cardboard Robot Halloween Costume of Doom (the making of)
Cardboard Robot Halloween Costume of Doom (photos)
Links to MORE custom Robot Costume creations! (with instructions!)
Underneath those hot costumes, you'll want to wear underpants made of this cloth:
Image source: Flickr set of London Mummy
Of course, inside that costume you'll get thirsty! So keep some rum handy, in case you run into THIS robot:
Image source: Flickr set of Sanchome
Hopefully, you'll never have your severed head grafted onto a REAL robot body, like me!
Image (click to enlarge) from the upcoming short film, The Drunken Severed Head Show.