My pockets weren't deep enough for nucs so i'm getting into thin clients

I'm adding puppy linux 64 bit and removing from the operating system anything i don't want or need for crunching ( It is easy to do with linux puppy. There is a "click on" to do it built into the OS. You add boinc by using the puppy package manager. There are a few versions in their for specific projects so watch what you click on, There is a general one that puts both the client and manager in your system.

The main reason I bought a few is because I might have to shut down my bigger machines during the cooling season and these only draw 5 to 15 watts depending on load.

Example ( this one is on ebay )

HP T510 Thin Client VIA Eden X2 U4200 1GHz 16GB SSD 4GB RAM No OS

Price: US $32.50 Shipping: $14.23

Intel NUCs are definitely overpriced.

There's a 16-core Intel Atom server CPU that looks neat. (Goldmont? Denverton?) I'm waiting for Intel's 10nm+ Atoms and Xeons before I build more systems/servers. (Been waiting for so many years...)

$600 for that NUC isn't a good value, honestly. Intel 10th generation is still built on Skylake microarchitecture and runs hot, even the lower power SKUs. The NUC enclosure isn't really designed for good heat dissipation. For the same price, you could build a dedicated cruncher that's way more powerful and quieter, or you could spend half that and still build a good dedicated crunchbox.

Good point, how do the Pi's stand up over time, these are business type systems and they are pretty rugged. Down side is they usually have only one core. Their power draw and the amount of heat they put out is low. I put one to a torture test and it was still cool enough to hold my hand on the heat sink. They are fan less and can mount on the back of a television or monitor.

I am also looking to set up a few as web surfers and general systems for Christmas presents for the grand kids ( so they don't ruin mom and dad's systems :o)

What else are you going to get for that price? Tablets don't hold up to crunching