One of my older academic projects was “BluePad” (2009). The project mixed my interests in electronics and embedded programming. It was an oldschool gamepad controller enriched with bluetooth communication module. It was used to connect to mobile phones running Symbian OS (i.e. Nokia N95). The project consisted of two parts: first one was the connection of bluetooth module (BTM 112) with an old gamepad (Nintendo rules!), the second was the driver written in Symbian C++. The driver let the user find a proper device and pass the commands from the controller to the operating system. That combination worked great and let the user of mobile phone take pleasure of gaming without challenging the numeric keypad.
Nowadays I’d bet that because of the high price of the bluetooth module, there are many “made in China” alternatives :]