There are heaps of rhythm guitar apps available now (even a Guns 'N Roses-branded one), but tapping your fingers on an iPhone does get pretty tired. Strumming on your iPhone inside a guitar though—now there's an idea.
It'll come as no surprise that the Fingerist originates from Japan. With an inbuilt speaker (or line-out for plugging into a speaker), all it requires is 3x AA batteries. You can rock out on your iPhone or iPod Touch's guitar apps for six hours until the batteries wear out, and then you're back to drumming your fingers on a touchscreen like everyone else. [Evenno via Geeky-Gadgets]