Here is a pattern for a willie warmer, which can be seen on
this site along with other anatomically correct knitting projects. We were talking about this on a different thread a little while ago (sometime in early February?), but I searched like crazy and still couldn't find the thread... however
here is another thread on a related topic.
Unfortunatly, we don't have pic on here of a willie warmer being modeled, in case your DH is interested. It could bring him fame and fortune!