My old university has three /16s, and a bunch of other IP blocks, so gave public IPs to everyone (though they now seem to be using private IPs for some purposes

My old university has three /16s, and a bunch of other IP blocks, so gave public IPs to everyone (though they now seem to be using private IPs for some purposes). I never looked at how the public machines were allocated, but it did make picking out traffic from the residences trivial - they reverse DNS resolved to <userid>.<college.>cam.ac.uk