If you get a chance check out a colleague of mine named Doug Brown and his wife, Annie on the Today Show discussing their book, "Just Do It: How One Couple Turned Off the TV and Turned On Their Sex Lives for 101 Days (No Excuses!)."
There is also an article in The New York Times on it.
I haven't gotten my copy yet, but I am anxious to read it and not because I was mentioned (not by name) a few times; but when you get it, look for the passage about the colleague who was inspired by the Browns' sexapades then ended up pregnant because of it.