Yesterday I started something I've wanted to do for quite a while but never got around to due to lack of tools. Making a database of my book collection.
I started off with Libra. A free database for Windows that allows you to scan barcodes using your webcam. It then trundles off to Amazon to pull out the information on your item. Initially I tried using it with my XBox 360 webcam with no luck. Happily my Logitech Quickcam 4000 works just fine although I did just order a cuecat from Ebay to make things even more straightforward.
After I'd been working on this for a few hours I was told about a wonderful web project called Librarything. This lets you create an online database of your book collection and share it with the world. It also features some very nice social networking features. Better yet it allows me to take a csv export from Libra and import my books neat so I now have a local database and a nice searchable online copy.
I haven't finished yet but my current catalogue can be viewed here. You can also see a random selection of books (Complete with Amazon links) over to the right.
And of course once I finish my current collection keeping it up to date with any new books becomes trivial.