Also, I wouldn't bet on the durability of things like the optical drive mechanism to take continual vibration and sudden shocks a whole lot of times, and there are probably a couple of dozen very tiny connectors inside most laptops, and they're just pressure fit on. Enough of just the right bumps and they could pop loose.

I still say, either access your work machine from home, or carry the work with you on a thumb drive (you can get 16GB thumb drives now pretty cheap) or a small hard drive (160G 2.5" externals will fit in a pocket and are around $100 and are very tough).

Regardless of where you hold your data, if it's on ANY kind of a device that you carry around, ENCRYPT IT. You have to assume that if it's on a portable device, it will be stolen at some point. Encryption is free, go get a copy of truecrypt.