I know Adium can insert links from some browsers by itself, but I just found a script at the Adium Xtras site
which offers much more fine-grained control over inserting a link from any browser, with the page name's descriptive title linked nice and clean, instead of the long ugly URL you get from copy/pasting. As you can see, specific commands are included for all the major browsers (and even some not-so-major ones), as well as a catch-all Default Browser command. The ones I can test seem to work pretty well, though I'll admit I don't have any copies of iCab or Netscape lying around. Enjoy.