BOINC is a program that lets you volunteer your idle time on your computer or phone to cure diseases, study global warming, discover pulsars, and do many other types of scientific research. It's safe, secure, and easy!
Volunteer computing supplies more computing power to science than does any other type of computing. This computing power enables scientific research that could not be done otherwise. Volunteer computing also encourages public interest in science, and provides the public with a voice in determining the directions of scientific research.
As seen in Chapter 5 of Citizen Science by Caren Cooper.