PLEAC is a good resource as long as you watch out for the Blub paradox. “But when our hypothetical Blub programmer looks in the other direction, up the power continuum, he doesn't realize he's looking up. What he sees are merely weird languages. He probably considers them about equivalent in power to Blub, but with all this other hairy stuff thrown in as well.” [<a href="http://c2.com/cgi/wiki?BlubParadox" rel="nofollow">http://c2.com/cgi/wiki?BlubParadox</a>]