The notion of using a phone to power a computer isn't new -- we've seen companies like HP and Motorola try, and ultimately fail, to make it a reality for years. But that's not stopping Apple from considering the idea. The USPTO issued a patent filing this morning detailing how an iPhone, or an iPad, could be used to power an ultraportable laptop, AppleInsider reports. As usual, the patent idea likely won't end up turning into full-fledged product (it was originally filed last September). But it gives us an idea of how Apple is looking at the future of mobile devices and ultraportables.