I read "The Mary Sue" (http://www.themarysue.com/) regularly and I've always loved the different character logos they have on their banner:
http://www.themarysue.com/the-mary-sue-logos/#0

They don't have one for Gadget however, so I fixed that! It's not the best quality, but you get the idea. This is intended entirely as parody/fan art and I do not wish to profit from it in anyway.

Go check out the original artist's work!
http://cgoudreau.com/
http://cedreau.tumblr.com/

http://www.themarysue.com/ is copyright its respective owners