Oxford colleges have already been discussed, but which is the best one at Cambridge. I'm going to say
Christ's - Academic
Emmanuel - Social
Trinity - Wealth/Rep
You can only have ONE!
I've never been to Cam., but judging from everything I've heard/read/seen, I would choose one of Gonville and Caius or Trinity. Probably Gonville and Caius, due to all the tradition there
Trinity probably has the best website. Johns', whilst it has lots of very useful information, is a bit basic.
Trinity doesn't have a wedding cake though!
Well, it's New Court but some people call it that.