Here's an idea.... Get on eBay and buy one of those Chinese packs that come with two 1800mah batteries and a wall charger that charges the batteries out of the phone. Then do what I am trying.... I taped the two Chinese batteries together, back to back, to equal the thickness of the htc ext. battery. So what you can then do is charge one set of batteries while the other is in the phone. Then use the phone til it dies then swap batteries. Only problem is that the dual battery "pack" will have to be flipped once one of the twin batteries is charged.
Heehee, I'm a cheap skate...
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