Chippy as gone Green. He has created a new page to demonstrate how to use the Sun to power our UMPCs and other electronic devices. I always have found this idea interesting up to the point that I have been using solar energy to power my landscape lights for the last 3 years. And recently I recommended to install Solar Security Lights like this one to a company and they bought few of them.
Like Chippy I have been thinking about power my UMPC with Sun but I have to confess that I'm not traveling that much so I have not gone so far in this project. But what amaze me is how many things have in common good friends.
Good luck in your new project Chippy: Solar UMPC.