Online-REPs-and-REPLs

This is a list of sites you can use to interactively try out programming languages online. Read more about REPLs at Wikipedia.

Some of these sites aren't strictly REPLs since they don't maintain state, those sites are probably more accurately described as "REPs"?

Am I missing something? Let me know.


See also:
  1. http://stackoverflow.com/questions/49092/online-interactive-consoles
  2. http://codepad.org/about
  3. http://ideone.com/faq
  4. http://repl.it/#:help