World Maths Day Challenge
Announcing a new Challenge slot! To celebrate World Maths Day, and our new PPS-DIV sub-project, we'll be running a 5 day Challenge from 10th October 18:00 UTC until 15th October 18:00 UTC. Other Challenge dates are unaffected.

The Fermat Divisor search is especially designed to have a better chance of finding a Fermat Divisor. It has a limited number of candidates to check, and once they're gone, the project is over. A new Fermat Prime Divisor earns the finder a rare
badge. The project has found 18 primes so far, but no divisor.

For more information and discussion, read this forum thread or join our Discord server. 12 Sep 2019 | 11:52:29 UTC · Comment
To all Prime lovers - new sub-project called "Wieferich and Wall-Sun-Sun Prime Search".

Edit your account PrimeGrid preferences and check CPU and/or GPU.

The sub-project discussion forum can be found here.

I have not run this sub-project yet and yes there is a new badge
See forum discussion here.
If you are going to run "Wieferich and Wall-Sun-Sun Prime Search" on CPU then the project organizers are currently recommending setting the threads to "no limit" in the project preferences page. The same page you'd choose this subproject. This will utilize your entire CPU. The tasks are very long running on CPU.

Each task will take a very long time on CPU. I saw a report of an AMD 3950X utilizing all threads taking something like 16 hours. My 1950X utilizing 4 threads was at 10% after 7 hours. Ouch. Personally, I could not justify that power utilization. My 1080Ti is taking about 18 minutes. 3080 is around 5 minutes, and 3090 around 4 minutes.
PrimeGrid updated their Fastest GPUs page to include the WW subproject:

Current ranking as of 11/30/20:

I've found that this project uses basically 0 CPU usage. More CPU resources for other projects. ;) I currently have it running on my 1080TI at 60% power limit set in MSI Afterburner. Using about 180 watts.
PrimeGrid made a HUGE update to the LLR software in September.

If you find a prime in these subprojects then you'll always be the first one to crunch the task and you'll get all the credit. How exciting!

Project currently converted to LLR2
GCW (2020-09-19)
SR5 (2020-09-19)
DIV (2020-09-25)
PPS-MEGA (2020-11-03)
They also implemented a bunch of fancy error checking and security checks, so verifying returned tasks are down to 1% of the time or less. Saves a lot time, and you'll get many more completed tasks -- Nearly all your CPU time is going to new prime numbers candidates instead of double checking. Read more about this and how it is accomplished here on the PrimeGrid forums:

I made it to 1 million on the new WW project. Woot!
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WW sub project will be ending soon. If you don't have your badge goals hit yet, you may want to get on it.

It should be at the bottom of the project list.