For a majority of my unlogged dives I used a Suunto Gekko. I think I can download the dive data (which I agree would be great to have), but after doing some investigation it appeared that I needed a special cable. In hindsight, I should have purchased a better computer that made this easier.
The "special cable" is required for many computers (and almost all of them are different and overpriced!). I got mine (Gekko/Vyper) from a supplier in Germany on eBay for a fraction of what local retailers were asking and, if you look around, there's a utility (geeko2vyper IIRC) that fools your Gekko into thinking its a Vyper. Using the free software from suunto's website to can download, log and analyze the data.
I log my dives but in a minmalist kind of way - I'm interested in depth, time, exposure protection, amount of weight needed etc. and tracking skills development/needs.