i have one
I have one(Power Mat), use it for my HD2. Works very well. Seems to help with battery life, as it seems to charge better a little bit slower. takes about 45 minutes longer the charge my hd2, but lasts hours longer since i got it. Still waiting for a powermat battery cover for my g2, but havent seen one yet. Got mine at walmart for 80 bucks, i think it was well worth it. very easy to charge, dont have to worry about plugging it in all the time, as you just set it down, and it charges.
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