griffon wrote:

I have a big stack of concrete blocks here (the type with two holes in
them) that are both a collection place for wasp nests and an eyesore.
I have tried to figure out some way to use them in the gardens, but
have yet to come up with anything. I would love to find a use for
them to get rid of the stack. Any ideas?

Compost bin. Very slow to bleed off heat.