2. Logic 3 Game Boy Advance SP Solar ChargerYes, its another solar charger that can power up your Game Boy Advance SP. Just hook up this puppy to your GBA SP, Nintendo DS or PSP, put it in sunlight or direct indoor light, and in about four hours youll have a fully charged battery. Not as sturdy as the Solio, doesnt store any power and wont work with other electronics, but it costs a lot less, works fast and comes with all the cords and adaptors you need. Unfortunately this product was only distributed in Europe, but if you search for "Game Boy Advance SP"+"Solar Charger" youll find many websites that you can order it from domestic and internationally.
3. Game Boy Advance SP Mini Winding ChargerIntended mainly for emergency situations, all you need to do is plug this device to your GBA SP and turn the crank. After about 8 minuets of crank turning and hand cramping youll get a 30 minute charge to the GBA SP battery. Dont overdo it though, the unit gets hot and comes with a warning that if you crank it for 15 minuets or more it will overheat. This one is also only distributed in Europe, so youll have to put in your favorite search engine "Game Boy"+"Winding Charger" and youll find tons of em.
If you have a Game Boy Classic, Game Boy Color or the original GBA, then you're likely using regular AA batteries, which are downright terrible for the environment and rarely disposed of properly. The best and most economical thing to do is to get yourself some rechargeable AA batteries and a charger. I recommend getting two sets of the rechargeable batteries, so you can keep one set in the charger while your using the other set in your Game Boy. If after all this your still using regular disposable AA batteries, at least recycle them properly.
Lets all work towards saving the Earth while playing video games!