Picked up a Seagate FreeAgent GO 500GB from Staples. They have it on sale for $99 down from $130 I think, and you get a free Docking Station for your desk. I actually bought another docking station for $10 so I can leave the USB wire hooked up to the HD2500 when I close up the case for the night.
Here is a link to the sale
For some reason the $10 off coupon code isn't working online. I just went into my local Staples and bought it there.
The reason why I picked out this HDD from the others is that it uses a Notebook hard drive, and you can power it straight from the HD2500 itself or a powered USB hub. No need for power cable and wall wart hogging space on the power strip.