I think, you are right,misterpat, it would be a little over-fragmented. But I don't see how we could have productive forums otherwise. While people from all disciplines could chat together under, say, cities, I don't think it make much sense for a Biology and an English student to write in the same forum regarding the academic aspects of grad life. But maybe, dividing things into a few compartments like natural sciences, humanities, social sciences etc. could still work. ( I think this is also what belowthree meant, I just wasn't 100% sure) But to be honest, I don't think "tiny enclaves" is such a bad idea. But that may be because I am in poli sci, which is a pretty happening community in this forum.