I made this 3' x 5' poster ten years ago for a CDC exhibit at Emery University, Atlanta GA. The whole show was about the importance of washing your hands to prevent the spread of bacteria and viruses. 

I think it's a fun poster that highlights the fact that washing your hands isn't only important after you go to the bathroom or touch raw meat. There are many other reasons to regularly wash your hands, small things, things you might not normally even think about, like money.