I have been toying with a similar idea a while ago. What I have come up was a simple read->eval loop, written in Perl. I was not very proficient at Perl at a time and this was done only as an exercise to learn some new things in Perl (Well, I'm not proficient at Perl even now ;)

Anyway, I have called this thing perlsh which seemed to roll off the tongue nicely ;) If you want to have a look at it, you can find it here (zip format)