What is the best way to power a usb device with 2 batteries?
I wish to power a plasma ball ( like this one http://www.amazon.com/USB-Plasma-Ball/dp/B0052GSQ8A ) with just two batteries. The whole minty usb charger seems like overkill and meant for smartphones. This is a simple device that runs on 5v and 350ma. But I could not find any instructables anywhere for this.
I do not mind using 3 or 4 batteries if need be. Any link or suggestion would be greatly appreciated.
Thank you in advanced.