How about creating a Computational Logic stack exchange site?
It would involve the theory of using mathematical logic in computer science and in formal methods (yes, another name suggestion): theorem proving, model checking, lambda calculus, type systems, term rewriting, SAT and SMT solving, BDDs etc., and their application in concrete software artifacts like Isabelle, HOL, PVS, Agda, Coq, Twelf, Spin and others.