Are there any popular programming languages whose preferred written name contains a space? Object Pascal and Visual Basic are the only ones that come to mind. (Objective-C dodges it by a hair).
Common Lisp. If you want to count things like <architecture> Assembly as languages, e.g. x86 assembly.
There was also Component Pascal. And Franz Lisp, if you accept dialect names. Also, OCaml used to be called Objective Caml, if I'm not mistaken.
Lisp-Flavored Erlang, though LFE is probably more commonly written.