Perhaps you want to connect various modules to Xadow. For example, a IR sensor which can detect whether someone is here, You can connect the sensor to this Breakout Module.
Xadow is a though small but perfectly formed Arduino(TM) compatible board series containing several modules. It's a kit extremely suitable for space-sensitive projects such as wearable devices & arts designs, which have higher request on size, weight and flexible cascade connection.
You can find more modules here.