A clip on controller for the Nintendo DS is being built which slides in to the BGA cartridge slot. What the controller does is ads 4 input buttons which allow you to jam away to guitar hero. To keep the DS safe a strap is also included which keeps the DS attached firmly to your hand. When hitting the buttons on the guitar you can use your other hand to strum the guitar strings on the touchscreen.
We began prototyping ideas for Guitar Hero on DS in early 2007 ¦ We quite frankly didn't know whether it would be possible to bring the core essence of the franchise to handheld and have it actually work. It was 20-something gameplay prototypes that were built, all trying different mechanics and uses of the hardware. Some were pretty cool, others were total disasters!
It looks like quite a funky add-on for the DS and could sell quite well. 20 licensed songs will be available which will also make use of the microphone.
Via: Geek