My friend, Rick, spent a few hours and created a terrific website called Big Needle. It is a place for the medically inclined to gather, featuring quizzes for fun and edutainment (a stupid word I feel bad for repeating).
I’m adding a link in my sidebar too Big Needle, and I hope you give it a chance. The link requires a registration.
Rick can always use question writers, and lurkers are, of course, welcome.