Free program Folding@Home has nothing to do with laundry, even though that's the only kind of folding most of us ever do at home. Instead, it has to do with health and medical research. Folding@Home helps scientists gain a better understanding a wide range of illnesses including Alzheimer's, Parkinson's, Huntington's, cystic fibrosis, and other serious diseases.
"Folding" is something proteins do. In a nutshell, it's a process whereby the protein transforms from a random-looking string into a functional three-dimensional structure. Sometimes proteins can fold incorrectly, and this leads to a host of degenerative diseases. If this description sounds a bit fuzzy, it's not just because it was written by a computer scientist trying to explain biology: It's also because it's an incredibly complex process, which has not yet been fully understood.
One way to understand protein folding (and misfolding) is to simulate it. Such as simulation is a virtually unlimited computing problem: The more processing power you have, the more complex your simulation can be. And this is where your humble computer (or awesome gaming rig) enters the picture.
Rather than invest in a huge supercomputer, Folding@Home harnesses the collective computing power of Windows, Mac, and Linux computers, as well as Playstation consoles. Each of these platforms has a Folding@Home client.
I evaluated the Windows client. On the surface, it looks like a screensaver with a simple configuration interface. It gets a small chunk of work from the central Folding@Home server, crunches away at the problem, submits the result and then gets a new chunk of work to do. Multiply this by over 460,000 active clients, and you've got one impressive supercomputer.
One thing I like about Folding@Home is that you constantly see results. The project has been active since October 2000, and since that time, over 70 research papers have been published using its data. On a more playful or personal level, you can set a username for yourself and track your own personal contribution over time using the project's website. You can even join a team and compete against other teams from around the world. The teams page shows some formidable work done by various computer enthusiast groups and overclocking forums.
You may think having an application use your processing time would slow down your system, but Folding@Home was built to be extra-considerate. It uses the lowest possible processing priority, so whatever other task your computer has to perform is considered more important. In my testing, I could feel no slowdown at all, despite the Folding@Home client utilizing 41-46 percent of my CPU time while I was working.
Since Folding@Home does make use of your CPU, it can cause some increase in power consumption. When your computer is running on main power, this should not be a concern. It may become an issue when you're working on a laptop in battery mode and every extra minute of battery life counts. Fortunately, the client can be configured to pause work while on battery power. Note that this is not enabled by default, and the client will keep computing even while on battery power if you don't set it to pause.
As a client, this is not a very exciting application: You can get it to display a cool-looking 3D molecule on your screen, and that's about it. The excitement comes later, when medical advances fend off life-threatening diseases--and you know that you helped find the cure.