Ashton Kutcher. Kutcher became the first Twitter Celebrity after joining in January 2009, when the site was getting ready to make the leap from tech-savvy coffeehouse to household name. He got tons of publicity for becoming the site's first user with 1 million followers -- a distinction he won after winning a race to seven figures with CNN. He also became a savvy investor in tech startups. He's now 23rd on the site's popularity list, with almost 14 million followers.