According to Ubergizmo, MSI debuted a solar-powered laptop and MP3 player at CeBit 2006. Aside from running on solar power, these devices can also be powered by a lithium-ion battery or via an A/C adapter. PCWorld also has an article, citing that the company doesn't plan to sell these products, and is just experimenting in ways to provide a portable solution for remote areas. The concept would be too expensive for mass production at this time.
"The lid of the laptop is covered with solar panels so that even when it's closed, it's still gathering the sun's energy. The system needs a voltage converter to adapt the output of the solar cells to the laptop's battery charging circuitry, says MSI."