Alcohol was permitted in residences at my alma mater. One floor in my dorm (infamous for heavy drinking) had a kegerator, threw several beer bashes every year with kegs, played drinking games, etc... In the late '90s the administration started cracking down, though, so I don't know what the current rules are.
I spent a summer at Trinity University in San Antonio about 10 years ago. They have some pretty strict rules... some dorms are wet, others are dry (all the freshman dorms are dry). In the wet dorms, you can only have beer and wine, only if you are 21+, and you can only consume it in your room. (Most dorm rooms have balconies - I don't think you can even take your beer onto the balcony.)
A Trinity student told me a great story, though... He and his suitemates threw a party where they had trash can punch. During the party, the RA and a couple of his buddies came knocking. "Open up! We know you have booze in there!" So they figured they were busted... until the RA added, "If you give us some, I won't write you up!"
