I have been running the SETI at Home program on my Macs for about 15 years but I have only had a reasonable number of machines at certain times (when spare machines were available for various reasons). I currently have a varying number of machines dedicated to the task - sometimes just 2 or 3 machines and sometimes more - so my output varies significantly over time.
A few of my colleagues at Otago University (and a few from other places) in the past used their Macs but my rate isn't very high now - at its peak my SETI project had about 30 machines. Check below to see my current status. You can check my latest stats at the SETI site.
In the tables shown below my best stats for the classic project (before 2007) and some significant milestones for the new one are shown in bold, and significant stats for the new (BOINC) project are shown in red.
Current and Previous Stats: OJB
1. Unfortunately, the large lab of computers I have had in the past is no longer available, so I am really just "cruising" with about 5 to 10 older machines. That's why my stats aren't as good as they were.
2. Indicates results from the new SETI at Home BOINC system. At the end of 2006 I have just temporarily acquired some faster machines, so my SETI effort should improve soon. At this point my computers have done more than 21,000,000,000,000,000,000,000,000 floating point calculations!
3. I temporarily have (or did have) a few multiple processor Intel Macs running BOINC at this point, so my total rapidly increased while they were still running.
I also run the MilkyWay@Home project (also avaliable through BOINC) when I can't get enough SETI data to process (for example if the SETI servers have some down time or don't have new data for any other reason). Here's my results for this project.
I also run the Einstein@Home BOINC project. Here's my results for this project.
University of Otago Group
I set up the the University of Otago Group so that SETI users at the University could pool their results into a group. Check the University of Otago Group here at the SETI site.
Current and Previous Stats: University of Otago Group
4. Indicates results from the new SETI at Home BOINC system. Some people have added themselves to our group and contributed a really impressive number of results.
SETI Goals: OJB
5. Indicates targets for the new SETI at Home BOINC system. Targets for the new system are difficult to compare with the old (classic) system.
The University of California Berkeley runs the SETI at Home project to capture and analyse data from the world's largest radio telescope at Arecibo and look for signs of intelligent life on planets orbiting other stars. Because of the huge amount of data analysis required it isn't practical to have the data analysed by a single computer, so the Internet is used to distribute data to a very large number of smaller computers (Macs, PCs, Linux computers, Suns, etc).
Many users (over 1.5 million at July 2015) connect to the SETI at Home web site and are allocated a chunk of data to analyse. When the analysis is complete (this takes a few hours for the average computer, but as the average computer gets faster this number decreases) the computer re-connects to the site to return the results and load another chunk of data. In total the system executes about 670 Teraflops (670 thousand billion floating point operations per second) and represents the biggest computing project ever (a total of one sextillion, or a thousand million trillion operations).
Of course, most people don't want their computer running a program to analyse astronomical data all day so the program can be set up to run as a screen saver. It runs when your computer "goes to sleep" and gets on with some useful work. Its also practical to run it permanently on computers which do light work full time, such as backup servers, especially if the priority of its process is reduced.