Catalog it all!

For mac users only- sorry windows people. Delicious Library 2. http://delicious-monster.com/
Catalog, list and keep track of everything you own. Great for cd collections, video games, DVD's, Pc parts, ect.

You can even buy a bluetooth scanner that pair with your Mac and use it to scan UPC bar codes. This would be great in keeping track of warranty's on electronics or movie collections. Also, if you house is broken into or if there is a fire, you have a complete list of your most important belongings.

We all have so much stuff now; mostly electronics. This makes sense to keep track of it all.