Tom Smith pointed this out to me - and it probably now holds my record for the shortest time between me seeing something for the first time and buying it.
It lets you catalogue your books, dvds, games, etc, and best of all if you scan (or type in) the ISBN number, it looks the details up for you on Amazon. Better yet, if you’ve got an iSight you can use it to read the barcodes. How cool is that?
I haven’t even got an iSight yet, but I suspect I may have one soon…