My mp3 player, because all my CD's are on there and I can claim them on the insurance, but it would take ages to get them all back on the mp3 player; and I think that's it. Everything else I can claim back, and I don't own much of sentimental value.
Wait! No. The stuff I've managed to get from gigs (drumsticks and setlists), and all my tickets/wristbands. Oh, and now that I've sorted all my stuff from my 18 years of life, a story that I wrote back in primary school where I was on a desert island with a couple of other people, one of them got their leg blown off by a landmine, but thankfully I had an artificial leg with me! And my yearbook.