Yes, imagine folding. Imagine contributing to society. This is one thing the acne ridden WoW kids don't imagine. They just sit there imagining getting that new uber pwnage chestplate! Losers.....
one could argue that they contribute to the economy because they are buying so much in many ways which is contributing to society. also one could argue that they are contributing to the society that is the world of warcraft society.
If you can afford to have 40 something boxes up and running, you can have them put to better use. Shoot you dont even have to stop gaming, you can throw two cards into each system, and have one run F@H while you game on the other.
Even something like an 8600GTS, which can be found for $40 will put out a good 2k points and its not too hard to the power bill.