Gba Rechargeable Battery

[Amarjit]

Along with announcing the Wave Bird, Nintendo stated that they were going to release a Rechargeable Battery for the GBA, yet they never have.

Therefore, what is the best un-official rechargeable battery currently available for the GBA (not SP)? I don't need something that's "hunking-out" at the back, like my previous one but something more like:

http://us.st8.yimg.com/store6.yimg.com/I/a...e_1775_64504985 (http://us.st8.yimg.com/store6.yimg.com/I/actionvillage_1775_64504985)

Preferbly, I'd want something to match my transparent GBA.

P.S., I'm aware of the Nintendo AC Adaptor that's available, but does not act as a rechargeable battery.

[Project E-01]

THe one ive got is a mains adapter with a hole in the top, and two square batteries. Basically, you slot one in the top of the mains adapter to charge it while your playing with the other in the GBA. Its made by Gamester, and the batteries just slot right into the existing case (and use the gba's own cover, so no bulk).