In my opinion google.com cannot be hacked. But i heard that google Bangladesh have had been hacked some time ago.
Nice trick to get more topic views As some have pointed out, this is an old "customized" search that Google created.
Try this one. http://www.google.com/webhp?hl=xx-pirate The customizations stick with the page. If you do a search on the page the results are formatted using the "slang" of the theme.