If You Were Crazy Enough To Get a Gadget Tattoo, What Would That Gadget Be?S

Extremely nerdy tattoos are popping up more and more these days. Not that you are crazy enough to get one, but let's say you blacked out after a drunken evening and woke up with a gadget tattoo. What gadget might it be...and where would you find it?

Keep in mind that tattoos of anything that falls under the nerd culture umbrella is acceptable—from physics equations to portraits of Bill Gates with the words "XOXO Forever" underneath. Bonus points if you actually have a tattoo in this category.