Tip of the moment: Check the springs when you change the batteries.
I recently got a Palm PDA as a present from my wife. I changed the batteries for the second time since I got it and rushed off to an appointment. Upon arriving, I discovered my Palm had reset and I'd lost everything. Investigating, I discovered one of the springs that's supposed to make contact with a battery was bent sideways. I fixed it and restored all my data upon my first opportunity. (Yes, as recommended, I'd done a HotSync just before changing them.)
[From my "Past Tips of the Moment and Past Thoughts" page. This was the eighth tip and 13th and final post overall. Although the page and the section on my home page stayed there through 2009, I let it stagnate and never updated it again, even though I didn't yet have a proper blog or other venue to replace it.
This tip refers to my first PDA, a Palm IIIxe. Unlike later PDAs, it used regular, disposable AAA batteries instead of a rechargeable one. It did have some way to maintain its memory during battery changes, but it was a very short term thing. — 28 May 2009]