I have. And honestly if I was in build a product and get something released because I'm building a business mode, I'd be using it I think. It's a pretty good fit for what I was looking for when I started.

Right now thougt I'm thinking learning experience with zeromq, and also I'm seeing how I can build something that can be used to scale an http application beyond a single datacenter/cloud and more. I actually find that pretty exciting and since I have young children and a good paying job, I'm still treating the product I'm working on as a hobby rather than a business.