Ask HN: how to find an interesting internship?

Hello HN readers,

I'm a french student currently studying Computer Science in Dublin (Trinity College), and I would like to know if you have some tips to find & get a good/interesting internship during summer '12.

For the record: - I enjoy mainly C/Python programming but I would be happy to learn something else (like functionnal programming for instance) - I enjoy solving algorithmic/math related problems (like those you can find at Project Euler [1]) - I don't mind if the internship is in a big company like Google or a small start-up. - I want to be useful, not a bring-me-a-coffee intern.

[1] http://projecteuler.net/