[hga]

MIT has a school wide UROP program (http://web.mit.edu/urop/) that generally grants credits during the school year and wages in January and summer, with the attractive bonus that a professor doesn't have to pay the stiff overhead usually required on the latter.

I would expect that as ramchip notes informal arrangements can be done most anywhere, although getting paid in any way other than experience may not be.

One maybe not so minor note: according to one school that is ABET accredited, only 210 in the US have ABET accredited CS programs. E.g. my home town 4 year public college doesn't have one, I'd have to go to a larger regional one 70 miles away.