Scratch my last post, just researched what the other guys were saying because they seemed scarily knowledgeable...
I underestimated the power of these passthroughs and mods, definitely don't use them on your pc or laptop usb port if you are not sure it can throw out enough juice per port. Check the overall power rating of the bus and then look at what you're using, or if in doubt get a usb-to-wall-jack-doodah-thingymebob-whadjamawammitjammer (sorry for the technical jargon, thats what they're really called) (honest) (make sure you pronounce properly when asking for it in the store)
anyway sorry for my previous post, got caught up on the possible pc issues and overlooked the bones of the matter.
Love to all!
Duncan