If you go to http://www.yougetsignal.com/tools/web-sites-on-web-server/ and type in google.com, you can see a list of all 144 domains on the same IP as Google. Some of them are rather odd:
www.54tz.info
baidu-inc.com
alexa.pp.ru
g.hixiao77.com
news.detroit-techie.com
washingtonhotelaudiovisual.com

That doesn't mean anything, I can point my domain googleluvlolcat.com to Google's IP as well.

I rather prefer http://whois.webhosting.info/ for this kind of information
Though not very accurate again, but still better.