Hi Günther,

about the Haskell Summer School,

who can participate and what does it cost?

As second (but related) shameless plug, we also have a two-week-long
summer school which is an excellent way to jump-start the above master's
program or to get quickly up to speed on Haskell for business or
pleasure. The course is in August, and the deadline is May 1.

http://www.utrechtsummerschool.nl/index.php?type=courses&code=H9

The link above has all the details (more than I do) on the Utrecht Summer School for Applied Functional Programming.

I don't believe there are any restrictions on who can participant, though the course is geared towards advanced bachelor's and beginning master's students. Since there are a limited number of spots, an applicant should try to put together a convincing application (e.g. write a good letter of motivation).

Regards,
Sean