Good question!
While many dream of that day quite a few have achieved it.
Amanda Congdon is one of them!
ABC News: Should You Quit Your Day Job to Blog?
Amanda Congdon, 24, one of the co-founders of Rocketboom.com, a video blog (vlog) that charges advertisers up to $85,000 a week to put their message on the site. Rocketboom launched in 2004 and now gets 300,000 viewers a day.