Ask HN: How to spell check HTML pages?

Is there a way to enable a web browser's built in spell checker to run on the entire page as opposed to just a form element? I'm specifically looking for a way to pull up an HTML document that I've created and see if there are any spelling errors on the page. I've seen some sites that will parse your page and give you a report, but that seems overly complicated. I'm looking for something like a bookmarklet or grease script.

What methods do you use to spell check pages that have mixed code and content (i.e. web templates)