Nell Scovell

Once, after a long week, I felt so insecure that I decided to make a list of people who thought I was funny even if I didn't think I was. At the top of the list, I wrote, 'Garry Shandling.' His early praise protected me like a comedy-writer version of Harry Potter's scar.

Jenny McCarthy has used her celebrity and sex appeal to attract attention to autism. And while no one questions McCarthy's determination and passion, many scientists have debunked her anti-vaccine message and her claims that a gluten-free diet can provide a cure.