PCs that will offer startup by mouse or kbd might do this but I've not seen that on USB. The current isn't generally sufficient for charging with the PC turned off.
is it possible to charge devices such as iPod, Psp, and cell phones without having the pc on but still pluged into the pc?
it has to be since computers at my school's Computer lab is able to do this.
I also read about self powered usb hubs
could i plug my devices into it and be able to charge them with out having the computer on or having the hub not being pluged into the computer?

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