It feels really good to be contributing to making the world a better place. Unless you are doing some heavy number crunching then you have plenty of computing cycles to spare. I give away up to 60% on my 2.8 GHz Core 2 Duo powered Aluminium iMac and it takes no more than 30 Watts of electricity; and has little impact on the work I do. If any delay is incurred then I just go have a nice cup of tea. "Donate the power of your computer when it is turned on, but is idle, to projects that benefit humanity! We provide the secure software and system that does it all for free, and you become part of a community that is helping to change the world. Once you install the software, you will be participating in World Community Grid." - ChrisDudman