Twelve South picked Tuesday to unveil a unique add-on to help Apple fans that travel with more than one device. PlugBug takes advantage of the changeable connector on a MacBook, MacBook Air, or MacBook Pro AC adapter to add a 10W USB charger. The add-on can charge anything up to the power levels of an iPad and is seen as a way to charge the tablet, an iPhone, an iPod, or other USB hardware without having to remember all the cables or charge through the MacBook.