OCaml is used for code verification tools too (Microsoft z3, CEA Frama-C, INRIA Coq, AbsInt Astree, Facebook pfff, ...) and for system programming a lot (Citrix Xen Toolstack, MLstate OPA, MyLife.com, MLdonkey, Unison, ...). If you have heard of OCaml only for finance, you have probably not searched enough.