My first commute! 1/2 mile or so to the Metro, then 19 minutes on that, then about 3.5 mile ride to work. To protect my laptop, I rigged up a padded container. For those who have ever gotten married or attended a wedding shower, you might recognize the green container as a "Pyrex Portable", designed to transport pyrex glassware. The cool thing is that it comes with pockets on top and bottom into which you insert hot/cold gel packs. Seemed the perfect bump buffer to me. So, I used that on the bottom (beneath laptop) and a spare tube wrapped around the laptop for a snug fit in the container.