Welcome, BigPete! 😀
Distributed Processing, is basically using wide spread and diverse computing power (many individual's PCs, multiple OSs) over a network (usually the Internet) to process work.
SETI analyzes radio frequency signals captured looking for specific patterns and anomolies that could be from a non-natural source, such as other life forms.
RC5 uses a brute force method to search for a specific encrypted key. This contest is sponsored by RSA, to prove how strong their encryption is.
Most if not all distributed projects clients will run the PC at 100% CPU utilization, but are set at the lowest priority, so anything that you do, whether it be gaming, word processing, or surfing, will get the PC resources it needs.
The only negative that I can think of is that there is more heat generated due to running at full load. this is only an issue if you have very poor cooling, as the system may be unstable.
Many people including myself see this as a positive feature, and use the distributed clients as a stress test on systems, as it will help pinpoint systems that would have problems under full load with any application.
Some of the positives are having fun, learning a lot about networks, PCs, overclocking, operating systems, games, etc. The fellowship of team mates, the thrill of competition with friends and other teams, having fun with statistics, and did I mention having fun? 😀
Others more knowledgeable can help discuss other distributed projects that are going on, some even have the potential to help understand and even cure some diseases. 🙂
