I saw this video linked on another message board. It's a rather interesting bit about an island that has a monkey population that has learned to like alcohol. They say that studies of these monkeys show some similarities to drinking in humans (For instance, the percentage of monkeys who don't drink alcohol is about the same as with humans).
http://www.ebaumsworld.com/video/watch/383561/
http://www.ebaumsworld.com/video/watch/383561/