Most of us are probably aware of the SETI@Home project, where you donate some of your computer's processor power to help unscramble data received by SETI.

I've just found a (comprehensive?) list on Wikipedia of similar cycle-donation projects. Since a fair few of the posters here have been utilitarian, I'm wondering if they can help with three questions:

1) Which of these projects are the most utilitarian and why?
2) Are the best of these projects clearly good enough to be worth the environmental damage of leaving your computer on especially for?
3) I've been warned that they make you a much more visible target for hackers. Can anyone explain the potential risks?

(obviously the second could annul the need for the first, but it's hard to answer without the first - and perhaps impossible even then)

I think the immediate goals are more pressing, since I don't see it as a certainty that we will make it out of this century alive. So we need to focus on core things like Biology and Energy, rather than astrophysics or climate prediction. Certainly there is room for all of the above, but we are facing a series of converging threats from emerging technologies, geopolitics, global warming, and terrorism. We don't need to be obsessing about any one of them, but rather we must focus on becoming resilient to crises of all sorts.

Thus, fundamental biological research is key. I donate my cycles to Rosetta@home, since low-level biology has wide implications for human enhancement, life extension, energy, and so forth. There are other competing protein folding projects, but this one was the most open and seems like the most promising. Though, I am willing to be convinced otherwise.

There are other sorts of things which can impact resilience more than biology, at least in the near term, but none of those have distributed computing projects to donate to. Examples: open source hardware, open source architecture, open source space travel, etc.

There are people interested in this sort of thing though, like these guys or these guys or these guys or these guys.

It would be cool to set up a new grid dedicated solely to providing free computing resources to projects such as these. It would be great if Arduino had huge computing resources with which to run genetic algorithms to improve its circuit designs. I'm sure other projects could benefit similarly.