I don't mean to limit it to us schools only, I just threw this together last Saturday. How do you suggest I make this work for all hackers at all schools?
I just graduated. I don't think you're going to hurt anyone's feelings if you accept any email address and let folks specify their school. This is a great idea though and I hope it gets use.
I'm at mcmaster, which has a mcmaster.ca address. I don't think it's possible to match on email address to allow all schools, so just ask for the school that someone attends. If you let some non-students through, what does it matter?
Matching *.ac.?? will enable a lot of European schools and universities. Not all cctlds have the .ac second-level domain though. Some countries have 3-letter second-level domains, so I have no idea whether .edu.[CC] exists anywhere.
Unfortunately, not all countries have a standard TLD for schools. I think the only way around it is with a whitelist of domains, but I'm not sure where the list would come from. Maybe someone has created it already? Either that, or use the facebook API.
Indeed, my university (in Australia) uses email@uts.edu.au, which is invalid. Interesting idea though - I like the upfront note/forethought about the cache settings.
If you whitelist @uwaterloo.ca, I know that there are a few uwaterloo students on HN.