I use my Palm V to keep a database of all my DVD titles, specs, upcoming releases, prices and where to buy. Very handy especially when you're out shopping. Saved a lot of $ this way.
There's something to be said about keeping all of your paperwork. Had a Panasonic A310 that suffered all of the common problems. I had to take in for the optical pickup to be replaced. The new one worked for about 6 months before it crapped out again! :angry:
Had pretty much all the paperwork...