While there's no shortage of musical "instruments" for the iPhone, the relatively small size of its screen makes string instrument apps gaudy because you don't have the room to strum the strings appropriately. The iPad is going to change all that by allowing the app size needed to strum (virtually) to your hearts content.
Developer touchGrove has previewed one of the first string instrument apps I've seen on the iPad. Called Air Harp, it turns your iPad into a 15-string harp. Now you can finally get down with your inner muse and strum to your Hellenic heart's content. The Air Harp app is pretty cool, though in no way as cool as the actual air harp, but until that Air Sitar app comes along, we'll take what we can get.