I've been using this handy little external disc drive for some time now, and am about to buy a second (I do a lot of digital photography!). It's pefect for toting as a ditital photo album, as you can just plug into any PC or laptop with USB slots. (nb, USB1.1 machines - you'll need two slots free to power the drive, as there's no external power supply).
Using the explorer on your PC or laptop is perfectly adequate to transfer files - the supplied synch software takes a little time getting used to, though, if you're not familiar with the genre. If you're moving between PCs, and need to keep everything up-to-date, the one-touch synch button makes life simple - it's quick, too.
The drives come in several sizes, but 60-80GB I find are most handy and cost effective(40-60-80-100-120GB are available, with prices that are fairer than other manufacturers' similar-sized external drives). Prices are coming down though, so go for the largest drive you can afford - it's cheaper in the long run.
If size is important, these drives are great - slim and sexy, they'll even fit into a suit pocket (but don't forget the cables!)
OK, I'm biased: I like Freecom stuff. But for ease of use, value for money, and, yes, looks, these drives are pretty hard to beat. If you like to keep your mobile office clutter to a minimum, go get one now - you won't be sorry!