This is a really useful memory stick with plenty of space on it for a decent wodge of files (esp text and photos). It's a bit of fun too -- cute, and instantly recognisable. Just be warned; the packaging features a little piggy path and I'm afraid that it was so sweet we didn't want to remove the pig from his 'home' for quite a while... (Sad. Yes. I know).
Pig is made of flexi but solid rubber, which makes this more robust than many memory sticks; easy to chuck in a pocket or attach to a keyring. It's also a very recognisable shape and colour, which makes it less likely to get lost and easier to find in a pile of gubbins (yes... we lose mem sticks all the time!)
The only downside to the shape is that this make Pig quite wide, so you can't plug it in to a USB port if the port alongside is already occupied, so we have to remove other USB cables to fit this in.
We use Pig to transfer and back-up files on PCs -- using various versions of Windows (Win7, Vista and even XP). Have had no problems whatsoever.
it's worth checking the price and size of the USB before you buy; they are available in 2GB, 4GB and 8GB I think, and more storage seems to be better value if you're backing up big files.
This would be a five-star product, if only it cost just a little less.