If you haven't already, I recommend checking out rlwrap, which you can use to run any ol' program that takes input on stdin and give it readline support. I use it quite a lot, and I have aliases in my .bashrc for wrapping various interpreters (like tclsh, sbcl, ocaml, and my own interpreters), but you can even use it to wrap /bin/cat and have a rudimentary line editor ;)