The Nokia N-Gage phone was essentially laughed off the market, but it was also weirdly before its time. In an age where mobile games are now trying to reintegrate tactile controls, this device was built for video games. It was built poorly, but still!
A modern €300 game phone-taco would rid the need for peripherals like controller clamps that you also need to pair to another external Xbox controller that then may or may not be 1-to-1 compatible.
I am very serious about this.
I'll go one step further and say: Make it flip like the PSP Go! 
