I Love You, Man (2009)

The mysterious male bonding ritual as portrayed here is actually at points shown at its most powerful, where a male friend can be a great ally, sounding board for ideas, fun. Of course, we all know this, but its interesting in this story of a man who never found it interested him enough to try to develop such friendships until his fiancee worries that he'll be groomsmen-less at the ceremony. Nicely done.