I do. Currently only in hobby fashion, but I also used it professionally when contracting for a company that was building a computation-intensive web platform on a Common Lisp (SBCL) backend. AMA.

Personally, I really like SBCL, it's my go-to implementation. I originally picked it because of performance considerations (hobby gamedev), as it compiles to native. But over time, I've learned to also appreciate the type inference and overall embracing the use of (optional by standard) type declarations to provide compile-time typechecking (as well as further performance benefits).