Western Digital Elements 500GB Portable USB 2.0 Hard Drive - Black

Good quality, good value, practically silent
I chose this product as I've had good experiences with similar WD drives used at my work, and unlike many other similar drives it stops spinning automatically after a few minutes of idle time. There is a slight delay the first time you try and use it after this as it spins back up, but for my purposes the auto-spin-down is a great feature - I have the drive permanently connected to a Marvell SheevaPlug which I use for automatic network backups.

Another plus point is that the drive is practically silent when in use - the first time I used it I had to pick it up and feel the vibration to convince myself that it was actually spinning! If you're looking for a drive to use in a quiet room this is definitely one to consider.

Western Digital Elements 500GB Portable USB 2.0 Hard Drive - Black

Works great with my Mac
Very quiet, simple, sturdy. I much prefer it's matt finish to the finger print magnet My Passport 'Essential' line. It also has a decently mounted micro USB port (recessed), a proper drive light (pleasing white LED from deep within) and an efficient auto spin down.

No problems when using it in Mac OS X(Leopard), I run a partition for my Time Machine backup of my MacBook Pro off with space leftover for another partition for general stuff. All easily setup in minutes from Disk Utility.

I'm well pleased with it.

Western Digital Elements 500GB Portable USB 2.0 Hard Drive - Black

Good Quality and Value
I decided to choose the "Elements" over "My Essential passport" due to the