Gmail recently added a spell-check feature. Now questionable words get underlined with red dots as you compose your outgoing messages. (And as I write this blog post, I notice Blogger has the very same feature -- so I surmise this is a Google thing, since Google owns both.) I don't really mind, but I do think it's odd how small its dictionary must be -- it doesn't even recognize okay as a legitimate English word. But my mind was truly boggled when I found the Gmail spell-check doesn't recognize the word... Gmail.
UPDATE: Mystery solved! As two commenters have pointed out, the red-dot-underling is Firefox's spell-checker, not Gmail's. Of course, that doesn't explain why even the most paltry of dictionaries wouldn't include okay.
As long as my commenters are solving small mysteries for me, riddle me this: Why do men's button-down shirts now often have a horizontal buttonhole for the bottom button? I've only noticed this over the last couple of years.