Why not go to Rotterdam this summer while visiting Holland? From the end of May until the beginning of September almost every weekend there is something going on in Rotterdam. Street theater, open air movies, dance parades and concerts on the water. You can find more information on Rotterdamfestivals.nl where you can link to the different festivals (culturele agenda).

If you're looking for a place to stay in Rotterdam the people at Use-It can help you out. Here is a list of hostels and cheap accommodation. Sleep-In De Mafkees seems like the cheapest option. For only € 10 per night (including breakfast) you can spend the night at an old skating rink near Central Station. And they have one very special suite: the honeymoon suite!