Do you have an idea that doesn't fit any of the other challenges? This is the place for you, whether you want to design and develop an app, create a data visualization, hack on an Arduino... or anything else you can think of!
Astronaut's Personal Computer (APC)
IBM Bluemix cloud and APIs
Wolfram Alpha APIs
Amazon AWS Lambda and Alexa APIs
Twilio API
Hardware:
Raspberry Pi 3
Amazon Echo
IBMs USB calbes ;)