There was a time when TinyURL was all you needed to get control of a monster-sized URL that you wanted to share with friends. Now, Google and Facebook are getting into the link shortening business, while bit.ly has launched a professional product for bloggers and news organizations. With so many Web pages being shared across social networks, e-mail and micro-blogs, shortened links have become virtual gate keepers to large amounts of content hidden behind those anonymous 15-character hyperlinks.