Sorry for the bad HTML, Chris. (It came from the eventlogs in DNN 04.08.00, but I probably didn't get all the tags from the copy/paste)

I've fixed the issue. For everyon else's benefit. The issue arose from a combination of a malformed end of script tag in an Text/HTML module in my "bottom pane" (that happened to be on all pages, except the admin and edit pages, of course.) I didn't see it originally because I think the DNN editor "fixed it for me by adding another </script> tag after the malformed "</script" entry.

The moral of the story is... Check your Text/HTML modules for malformed (or extra) script tags!

All is well in the world now... I hope this saves someone some grief in the future!