For Firefox users (IMHO everyone should use FF!), the following Dictionary add on is invaluable, not just here, but on all sites. Works by underlining mis-spelled words like MS Word. Right click to see options an correct.
Firefox should check spelling automatically (it does for me and with everyone else I know using it).
If you want to be happy for a day, buy a car. If you want to be happy for a weekend, get married. If you want to be happy for a lifetime, be a gardener.
I didn't know there was a spell checker on here. But then I preview and read through what I write which unfortunately a lot of people don't.
I don't mean offence to those who can't spell; it is more those who can spell but don't bother reading their posts to see that they have typed gobbledigook, which is irritating to try to understand.