When you start a business you not only want to have the domain name, preferably .com, you also want the youtube, facebook, twitter names as well, and also foursquare, tumblr, and everything else. It can take you hours or even days to check all of them and you will probably miss out on some.
Knowem isÂ a great site to auto check this for you instantly. Enter a name and it will check social media for the account names, over 500 of them. It will also check domain names as well. Really helpful tool when you are starting a brand.