While it was a very nice thought to include with the PS3 OS, it does essentially boil down to having to leave your console running when you're not actively using it.
As many have pointed out, there really isn't any tangible benefit on an individual level other than an increased Folding score and a contribution "certificate." It's basically out of altruism that anyone should be contributing to the project in the first place.
The two big drawbacks of running Folding during inactive run time is the electricity cost, which while reduced with later models is still not entirely negligible, and also the fact that running Folding basically puts your console into peak load mode, meaning it's generating a lot of heat and effectively burning the wick of your console in the process.
I did about six months of non-stop run time, cranking out a significant number of work units while I was at work and sleeping, which while nice, was probably the key contributing factor to my 60GB PS3 dying last year, simply from the thousands of hours of run time at peak load it had on it.







