Gordon -- I just bought this backpack for my laptop and have been extremely pleased with it:
http://www.ebags.com/ebags/downloader_laptop_backpack/product_detail/index.cfm?modelid=15025

I used to drag my laptop around on my bike. Then a realized that with a 1GB thumbdrive and by keeping my email on the web I didn't really need to do that if I had a computer at home and one at work.

Thanks, Paul and Bill. You two are reminding me that I am stuck in my old ways. I just bought a computer for my home office (with six other people in the family, the other computers are in high demand), and I think Bill's solution will work pretty well.

Thanks for sharing your story, Gordon. I plan to walk in the fall, in large part b/c I cannot justify the waste of resources for a 3/4 mile trip to school. As I understand it, however, walks in Ithaca are usually uphill. . . both ways. If and when we meet up at the AALS meeting this year, I anticipate that we both will be looking more svelte than ever. And I will consider one of those laptop bags. As we know, using shoulder bags is bad on the back (or something like that).