"Things You Wouldn't Know If We Didn't Blog Intermittently."
Thinkgeek has a t-shirt with the signs on it, and their relationships.http://www.thinkgeek.com/tshirts-apparel/unisex/generic/b597/
I first saw this a few months ago on The Big Bang Theory. Video here - watch for the oddly hypnotic rhythmic delivery of the rules.I love that show.
OH MY GOSH!!!! i know this shirt!!! Think geek is the best site ever