To clarify, as I fear we're wondering off here, I'm not so fussed about USB-port powering, as I know those a) are capped at 4.5V or whatever it is, and b) work - it is the mains socket adapters which I'm hoping to share. Of course, since many of these devices have different USB connectors on them (e.g. some mini, some micro), the whole thread is probably irrelevant anyway!!