Sean Callahan Started his company "Tweet Photo inc.", a website for people to use to post photos to their twitter page, the only marketing that he did for it was through twitter itself. Callahan's first message was aimed at finding 5,000 volunteers to test a future first version of TweetPhoto, which allows users of both Twitter and Facebook to share and comment on photos. His second tweet was an invitation to Rodney Rumford, asking the social-media entrepreneur and strategist from his native San Diego to give TweetPhoto a try. Mr. Rumford did more than that—he sent a private message to Mr. Callahan suggesting they talk business. Mr. Callahan picked up the phone, and Mr. Rumford officially became TweetPhoto's co-founder a month later. Then he invited graphic artists through twitter to submit ideas for a logo and urged people to vote for their favorite designs. The winner, Raul Padilla, earned $300 for a bubble-lettered logo beside two chirping birds. Once he got his company up and running from meeting people through tweets, all he had to do was get his name out there of his website. The chance came for him when TwitPic the first picture posting site for twitter, Mr. Callahan used keyword searches to gather the Twitter names of everyone who complained about the outage and sent messages inviting them to try TweetPhoto. Several people bristled at the tactic, but more than 800 asked for beta invites and, by April 16, there were only 716 spots left ahead of TweetPhoto's April 27 launch. Callahan then had his site up and running with followers of his own. Once the site was running all he had to do was market it through the social networking site. All of his followers then came to him through the "tweets"
