Originally Posted by Bacciagalupe

Unless you are a pro shooter or otherwise make money from your photography, 2 SLR's is overkill.

If you have the budget I'd pick up one (yes, one) Micro Four Thirds camera -- Olympus E-PL1 or Panasonic GF1. They're small, light, unobtrusive and produce excellent results as they use a DSLR-sized sensor. I'd couple that with a high-end P&S (e.g. Canon G11). If that is not an option, I'd bring one DSLR and whatever other lens(es) you need, plus the P&S.

For the laptop, if you absolutely need to edit the images while in transit I'd pick up a netbook with a large hard drive ($400?) and a small backup USB drive ($75). Alternately you can get a stand-alone hard drive (e.g. Jobo Giga) to copy images from the camera. Make sure to copy your image files to the backup drive regularly.

I would use a water-resistant handlebar bag to carry the cameras, e.g. Ortlieb. Those pop off easily and even have a lock, if you're paranoid. Put the cameras and the backup hard drive in there and pad it, and leave the laptop in the panniers.

There isn't much need for a hardshell case, if you get hit hard enough that a hardshell would help, your cameras are the least of your worries.

I also don't see much need to worry about theft, once you get out of the big cities, bike tourers rarely get robbed.