Here are some images i have done for people leaving. Usualy for the front of a football like t-shirt.
T-Shirt image of the 'Medical Research Council - Protein Phosphorylation Unit' logo re-worked for a real party girl!
T-shirt image for an itailan PhD student who discovered a new signaling pathway, who was the go-to guy for WNK related questions from all the new students following up his work.
Lame Star Wars 'head-replacement' poster of the people in my group. The principal investigator (PI) is of course cast as evil Darth Vader. The Senior post-doc (at the time - now a PI himself elsewhere) cast as the soon to be evil Anakin.