I don't know when it started, but for the last month or so, whenever I write something in either the Forum edit boxes or in the Article edit boxes my text is getting spell-checked, with (usually) the correct spelling popping up in a box if I first click on the underlined word. First I was using Firefox 3 and now I'm using Google Chrome, and they're both doing it, so I don't know if it's the function of these browsers or of some other mysterious capacity of the Internet. No grammar-check though, although as I recall from trying that out with my WordPerfect program (and glancing at it with Word), that sort of thing seemed more trouble than it was worth. For a fiction writer it was a real pain in the neck, especially with dialog....
Firefox has spelling built in, I believe. I'm not sure about anything else...