With apologies to GLaDOS, I think I'd have to use "Look at me still talking when there's Science to do!" as my catchphrase. I wouldn't be the type to run about throwing lightning bolts and using my kung-fu grip, and it seems like it would work for either a hero or villain. Although perhaps leaning more toward the villainous side of things, since they tend to enjoy exposition (and science) more than heroes.
"In brightest day, in blackest night, No evil shall escape my sight Let those who worship evil's might, Beware my power...Super Pony's light! "
From Green Lantern, hehe I couldn't think of anything else. :super::super::super::super::super::super::super::super::super: