Summary: The most portable external 1TB HD i've seen, period. Great flexibility in that it has both eSATA and USB. Really love the flat design - I have a WD Mybook with a stand-up design, which is kind of annoying to put inside my bag. Rugged enclosure makes it easier/safer to carry around, even if it is a bit bulky (but hey, it's 1TB!). Only con - need to haul around the power adapter, but I'm not aware of any USB-powered 1TB HDD's on the market.
Pros: Attractive Design, Easy To Setup, Easy to use, High Capacity
Summary: While I'm not a fan of most LaCie drives, the "Rugged" line has been very reliable for me at home and on the road. I often edit video with my laptop and I take my little studio all over the world. While the portable drives are great because you only need the firewire cable, I just needed more space this time, now that I'm working with HD video. My last project was humongous and I only wanted to carry one drive.
Pros: Attractive Design, Easy to use, High Capacity, Quiet
Summary: I bought this drive because I needed another backup for my image library. It's terrific, as are all my other LaCie drives. However, be aware that this drive looks like the other Rugged models, but is actually very very large. Same shape, twice the size (at least). I didn't realize this from seeing the photos of the drive online. Also be aware that this drive requires an external power supply.
Pros: Attractive Design, Easy To Setup, Easy to use, High Capacity, Quiet