Check out the photo under "Oops!" in the right hand column. According to the information I received, the sign is posted just outside Nairobi, Kenya. It may be a joke, but if not, somebody has a wire crossed somewhere.
The lady at the link above, "Free Online Books," was nice enough to put all my cowboy stories on her site, so I think it's only fair I put a link to her site as well. Check it out if you're looking for something to read.
