Buffalo Technology JustStore Portable 500 GB USB 2.0 Ultra-Slim Portable External Hard Drive HD-PV500U2/BK (Black)
I picked this drive up as a Gold Box deal for a competitive price. It's very, very easy to use. Unpack the unit, which is a black box with a USB mini port, activity light, and no other connections or buttons to worry about. Plug it in to the computer with the provided 14-inch USB cable. Windows recognized it straight away and it's good to go.
The drive manual and optional software is preloaded on the drive itself. You can load their specialized drivers and formatters if you like. I didn't bother. The drive comes preformatted in FAT32 format which is most compatible with different OS'es. The software includes a Windows program to reformat the drive in NTFS if you prefer.
I'm using mine to backup the music and video on my NAS at home, and to carry on vacation along with my linux laptop and camera so I can archive my photos each day.
Got a great deal on this external 500 GB USB drive. Haven't seen many Buffalo drives, so I don't know how they all compare, but this one ROCKS! Took it out of the box, plugged it in and just started moving files. Next time I need another HD, I'll definitely look first at Buffalo.
I received my drive very quickly and hooked it up to the laptop. It does exactly as promised. I don't notice any appreciable lag time, but I'm not really very aware of such things. For me it's important that it does what I need it to do (storage and backup) and does it easily. It was successful on all points.