Prague it is. I have ordered the plain tickets and all. I'll leave the 26th of April.

Things I should visit that I might miss or that aren't that well known? I was thinking of going to the opéra there as well, costs only €15 apparently.
About it being cheap, well it is said not be dirt cheap anymore like in the old days, but it's still cheaper than West-Europe. Also as Belgium is one of the most expensive countries anyway, that isn't quite the problem.