solar chargers for laptops

Anyone have experience with solar chargers for laptops? Know anyone who uses them for fieldwork in remote places? Thought I'd check with you guys before researching them on the web. Maybe I should email some of the people at the museum. I was thinking of getting a laptop and charger for Haiti since I'll be there a month. Though a charger isn't necessary since I can tap into my hosts' electricity while their solar/generator runs a couple hours each night. But they often have trouble with it and plugging in an extra device makes a difference in how much electricity is available. A side note - our tall flamboyant knitter is due next week! I gave a Haiti talk in her seminar today.