Hello from Reddit! Your rocket mass heater made the front page of r/frugal, which I subscribe to. I think it's great to see creative uses of resources, and thank you for taking the time to document your build!
Don't mind the early downvotes; because so many sites get promoted from reddit upvoting, there are users and website owners who actively try to game the system by downvoting everything except their own submissions. Quality material still seems to rise to the top despite early downvotes though.
