Today's priceless gem from Learning Oracle PL/SQL, the book I almost skipped, is the OWA_PATTERN package, which implements regular expressions in PL/SQL. Still not a language level construct, like in Perl, but it's definitely a step up from doing them in, say, C. I'd say it's comparable to the way TCL does it.
That was my number one question in the first of the two Oracle classes I took back in 2000. The instructor had never heard of them.
Perhaps more interesting to folks would be the fact that Oracle also has an LWP-alike, the UTL_HTTP package.
More tools added to my arsenal.