I have one of these guys plugged into the wall by my bed. Be warned that the USB ports won't charge anything that requires more than 500mA from the USB port - which includes obvious power hogs like the iPad and also other electronics like my Blackberry 9700. I think my Kindle also needs more power but have never tried plugging it into the usb ports, now that I think of it.

When I plugged my 9700 into the USB port, it said that there was insufficient power available for charging, and the little green light on the outlet strip started flickering.