I don't have many, as most of my possessions are mass-produced things that would be expensive to replace but the loss of which would not affect me emotionally (save for annoyance).
My data is more valuable than the machines it's stored on -- replacing my PS2 would cost only money, but regaining all my game saves would take many hours of work. I do have a few rare games and other items, but I have them only as a gamer and as a collector; I'm not emotionally attached to them.

If I had to answer with one item, it would be my signed copy of A Feast For Crows by George R R Martin. It's not signed by Martin, but it is signed by Michel Ancel (the creator of Rayman), Tim Wright (CoLD SToRAGE), and Paul Barnaby and Andrew Barabas (Bob & Barn, writers of the music for Primal). I took that book with me to read on the train to Videogames Live 2006, and there was a meet-and-greet afterwards. That book was the only paper I had on me, so I passed that down to be signed. Not only am I gleeful about having met Michel Ancel and CoLD SToRAGE, but it holds many lovely memories for me. I went to VGL with one of my friends, and we both had a lovely time there.
( Bob Todd whee, Mon 12 May 2008, 15:27, Reply)