On the other hand, if you have a game console, or have one of the higher-end graphics boards in your desktop PC, there are versions of many of the popular clients that will run an order of magnitude faster on the graphics processor than on a typical PC CPU, and can kick out results a lot faster than my old desktop.

It looks like the BOINC system communicates over the internet using HTTP, so you shouldn't need to poke any holes in your firewall to let it run. If you get a message from your firewall, that's likely to be one asking if the program should be allowed to access the network at all, which you want it to do.

It appears that it's only initiating connections with the server, not listening for incoming connections, so it should be pretty safe.

Started with The Clean Energy Project a few months back, which also uses Boinc; but fortunately it no longer crashes my PC and/or throws away the computed results.

I like looking at the Rosetta screen saver; trouble is, my monitor insists on going to sleep after a little while, so even screen savers don't stay visible for long.

Running these things mostly makes sense if your computer is on full-time. And do remember that being fully on rather than in power-save mode will make a difference to your electric bill.

It's still valuable work, but it's not nearly the "something for nothing" that it once was. At a rough guess, I'd say the costs of running SETI@Home on four hundred thousand machines instead of letting those machines sit idle are somewhere in the millions of dollars per month.

(The fact that something like this can get people to contribute that much cash, via their electric bill, to such a project is itself quite a remarkable thing, IMO.)

The research is conducted by public or non-profit orgs, and results must be released to the public domain.

True story: a friend of mine had her laptop stolen. The thief used it as it was, not wiping the hard drive. A couple of days later, it called in to SETI@Home, and the police were able to locate it by the IP address.

Some years the fastest supercomputers have been non-evil (The NEC Earth Simulator and other weather prediction machines need really heavy processing, and more recently some of the IBM BlueGene machines may be doing protein folding, though since they're at the weapons labs that may not be the case.) There's been a really radical increase in performance the last few years, largely driven by technology that was developed not for NASA or the military, but for the Playstation 3.

The current total speed of BOINC is about 1.1 PetaFLOPS, similar to the fastest machine on the Top500 List. Folding at Home is at about 5 PetaFLOPS these days - it took a big jump two years ago when the Playstation 3 client came out. On the other hand, the nuke labs do have a bunch of machines in the Top500 (and Top50) class, so they've got more total horsepower than we do. BOINC's largest application is still SETI (looked like almost half of their horsepower), but they and Folding both have a wide variety of research these days.

By the bye, the results from protein folding software will probably be extremely useful for early nanotech development; it's looking now like the initial phase of assembling nanomechanical and nanoelectronic components will be done with assembly tools made of proteins, picking up atoms or small molecules for assembly with their active sites. See the archives of Eric Drexler's blog, MetaModern for several articles on using biomimetic techniques like protein catalysis and macromolecule self-assembly for nanomechanical synthesis.

I work for Sony, and am very happy that we are making it so easy for people to contribute to this thing. (Even if I don't run it myself very often.)