Back in the late 1990's my friends and I used to donate our desktop's idle CPU and GPU to help SETI try and monitor radio singles to find extraterrestrials.
How far we've come since then. Now people can donate the power of their Android phones while they sleep to help power cancer research. Power Sleep is an Android app that was developed for Samsung Austria in conjunction with the University of Vienna.
By setting an alarm on your smartphone or tablet, you agree to donate your unused/idle CPU power to research labs. Because you have to be connected to wifi, it means you're donating free of charge, while a research lab who is working hard to find a cure for caner, can benefit.
Let's hope it's a big benefit for us all.