I wonder if this solution would work for other devices, perhaps with different values?

I do believe iPhone, Blackberry and possibly iPad/iPod are the only devices that work that way. For anything else I don't THINK it would be necessary. I do not guarantee, however.

Just to be precise, what you say is right but the value of the reference voltages in the data lines DO matter, infact they define the maximum current drawn! There are two possible configurations: 1) D+ and D- are both set to 2V: in this case the device will be enabled to draw up to 500mA when charging; 2) <strong>D+</strong> is 2V and <strong>D-</strong> is 2.8V: in this case the device will be enabled to draw up to 1000mA=<em>1A</em>; So you must be careful on what configuration you are going to use! In my case, for example, i hacked a usb charger that had 500mA as max output current, so I had to use the first configuration otherwise I would have burned my USB charger..! So in the end, what matters is <strong>D-</strong>, all the situation between <strong>D-</strong>=2V and <strong>D-</strong>=2.8V are enabling the device to draw up from 500 to 1000 mAmps. Hope this helped! :)

How do I know which configuration to use? Would it be written somewhere? I want to use iPod charger cable that came with my iPod...

The other thing that needs to be understood, is the device (whether it be iPhone or Printer) will only draw what it needs. Yes, what you are saying WILL enable the USB port to deliver 1A if a device that requires that is connected.

well that's handy information :p