I'm thinking of going to Roskilde festival this summer. Does anyone know what costs are like inside the festival. I was in denmark before and it was a costly experience, but that was in copenhagen. how do prices compare, say, to Glastonbury?

The prices at Roskilde festival are at least at same level as in Copenhagen (½ liter beer 35-40 DKK), most danes buy beers in Roskilde and bring them to the festival, the same with the food, which is horribly expensive, if you are dependent on it for the 4 days.