Books!
One of the really really great things about Roskilde was the days I got to spend lying in the sun reading 2 fantastic books: Northern Lights, the first in Philip Pullmans Dark Materials trilogy (why no-one has shoved it in my face whilst screaming ARMOURED FUCKING BEARS before now, I'll never understand), and Everyware by Adam Greenfield, which I'm going to re-read several times and spend a lot of time thinking about, because I suspect it's going to be quite influential on me personally.