Can I get one that says "I shook my family tree and a bunch of nuts fell out"?
I should probably also say that the last time I searched on CafePress for "genealogy", I got a bunch of hilarious results. (Sadly, not including any of my designs.) Here are some of my favourites:
I tried for a while to get some designs added to the WikiTree shop on Redbubble, and Chris finally told me that I could create my own shop for my designs, which I did.
There are also images at: