There are a number of projects people can build utilizing Raspberry Pi. Windows 10 IoT can be installed on Raspberry Pi, check out some projects on https://www.adafruit.com
Matrix Creator is a Raspberry shield that has some sensors that can be programmed for various things.
There are competitors to Raspberry Pi such as the Orange Pi and Banana Pi.
One of the coolest project I have seen so far. Open a door with facial recognition.