Visit the cool site codepad.org , where you can try out any esoteric programming language online which you never had the spirit to install so far. You can also view, try out or even modify programs that others have typed in previously. Supports the following languages: C, C++, D, Haskell, Lua, OCaml, PHP, Perl, Python, Ruby, Scheme, Tcl. (via verdelyi) ideone.com also supports a heapload of languages: Ada, Assembler, AWK, Bash, bc, Brainf**k, C, C#, C++, C99, CLIPS, Clojure, COBOL, Common LISP, D (dmd), Erlang, Forth, Fortran, Go, Haskell, Icon, Intercal, Java, JavaScript, Lua, Nemerle, Nice, Ocaml, Pascal, Perl, PHP, Pike, Prolog, Python, R, Ruby, Scala, Scheme, SmallTalk, Tcl, Unlambda, Visual Basic .NET, Whitespace. tryhaskell.org - specialized for Haskell, but does its job in light-weight JavaScript !