Not every gadget comes with an inbuilt solar charger, like the Puma Phone. XPAL's Solar Egg can do the job just fine, dangling from a keychain or belt-loop (if you dare) and charging to 90 per cent in four hours.
It doesn't even need a hot summer's day to do so, with XPAL claiming it works just as well in "medium levels of natural light". It's compatible with all types of gadgets with (presumably) a few cables included, and will be out in March. [XPAL via Engadget]