Tubeless tires have been a mainstay of the mountain biking world for years, and have inevitably made their way into road cycling as well. Editor's note: I run tubeless tires on my road bike and haven't had any issues and have felt the ride is better than my old clinchers. 

Complete article on tubeless road tires:

http://www.ilovebicycling.com/pros-and-cons-of-tubeless-tires-for-road-cyclists/