Simplon Youth Hostel is the one I was talking about, and the only one in Groningen. Click here . It's open all night, you can come in any time, and check in 'till 2 AM. The website also has prices in Euros, especially for Mudguard (I still prefer guilders...).
Mudguard: I just listed everyone who's interested in coming, even though they may not be able to come.
Susanne: I don't know if camping in your car is allowed strictly speaking, but it shouldn't be a problem. Where I live, it's paid parking until Saturday night, but just across the road in the next block it's free. You should be able to park and sleep there.
McGrath: I'll check out possibilities to rent schools or church halls next weekend, when I'm back in Groningen. Maybe if we agree to put on a performance, the students' cultural society will let us sleep there...:-)

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