It wouldn’t be difficult to put in a solar hot water heating loop. In northern climates puting a heat exchanger in the fireplace for a hot water loop can be done as well. Natural convection will circulate the water in the loop.
I’ve thought about it but rejected the idea because it might create more creosote during times I’m trying to get the stove temp up. Getting on the roof to do a winter/spring cleaning of a blocked flu is not fun.