I have known about this for quite some time... but I don't know why I have never tried it out. On facebook, you can change the language down at the bottom left of the screen. You click on English and then you can pick from many languages, one of which is English (Pirate). I decided to give it a shot this afternoon and I think I will leave it this way for a little while. It has brought a bit of joy to my Friday afternoon. It is quite funny. I only wish it would translate what people wrote to pirate as well... but that would be difficult to program I am sure. Here are some screen shots of my facebook so you can see what it looks like in "Pirate" if you have not tried already.
(P.S. for those who don't know... you can click on the picture to see it full size on your computer. I know you can't read anything on this little image)