It doesn't say why it's boldly stopped gridding apart from saying it's completed its mission to boldly demonstrate the benefits of large scale Internet based grid computing.
It suggests how to uninstall your grid agent, here.
One reader said: "I had 10 years & 28 days of accumulated participation since February 2002 beginning with a K6-2-450MHz and ending with a dual Xeon 3.6 GHz XP-Pro rig."
Surely there's more that can be done? ยต