I tried the data pins short trick today, i've heard of it before but never had to use it until now.

I was trying to charge my n900 of a solar battery/charger controller with a usb out, and wasn't getting anything. I tore the usb module out snice it has nice leads attached to it on a pcb, and shorted the data pins with a quick joint.

Hooked it up to a sepic tuned for 5v running off 8x nimh aa's in two sets of four (6v, ~4ah), soldered the leads to the output on the sepic and it charged now.

So what exactly does this mean in terms of mah's being put into the battery with the pins shorted, or time it takes to charge? More/less than the stock 1000ma 5v input?

I assume even if i get the full 2a my sepic is rated for, it should be fine, as i've hooked my n900 alone up to a 2a usb hub and nothing bad happened. I doubt its like a led where it takes all the current it can get, and all that really matters is the voltage (up to a point, super high current could short circut your phone).

Anyway, female usb cables are dirt cheap, this works just fine with an aftermarket usb cable as well. Get a cheap sepic, a lipo pack, and a female usb port and you got a nice little usb backup battery thats not rediculously overpriced, diy, and easy to upgrade parts/batteries.