KDDI’s au design project has churned out plenty of interesting cellphone concepts over the years, and it looks like its latest batch is no exception, with it enlisting the help of Yamaha to develop some cellphones that double as musical instruments. That includes the self-explanatory “Strings for fingers” and “Sticks in the air” concepts pictured above, as well as the “Box to play” synth / scratch pad combo, the “Key to touch” foldable keyboard, the “Trio in your hand” scratch pad / sampler, and the “Band in my pocket” device, which accommodates a number of accessories to create instruments ranging from a harmonica to a trumpet. What’s more, unlike some concept devices, KDDI actually had some working prototypes to show off, which you can check out in action in the video after the break (be sure to dig into the links below for some more pics and videos as well).

[Via textually.org, Trends in Japan]

Audi has dabbled in cellphone-to-car interfaces in the past, but it now looks to be stepping things up in a big way, with its new metroproject concept system sporting its very own, apparently self-designed cellphone / do-it-all device. In addition to doubling as a cellphone, the handset (which boasts both Wi-Fi and 3G UMTS technology) will apparently act as an MP3 player, a vehicle control system, and an input for the car’s navigation system. As if that wasn’t enough, it can also receive pics of any intruders snapped by the vehicle’s camera system, and it’ll even let you then keep watch on ‘em as they speed away thanks to the built-in tracking system. That’s, of course, if it ever actually makes it into a production vehicle — a possibility that Audi so far seems to be tight-lipped about.

[Thanks, David M]