Career Highlights: Clement heads to London with some unfinished business after coming up just short in the 400m hurdles at the 2008 Olympics. He was a slight favorite over fellow American Angelo Taylor but had to settle for silver after Taylor blew away the field with a time of 47.25 to top Clement's 47.98. Clement is hardly without his share of first-place finishes, however. He's a two-time world champion, winning the 400m hurdles in 2007 and 2009 before failing to make the finals in 2011. He holds the indoor world record in the 400m sprint, breaking Michael Johnson's mark in 2005. He won't only have Taylor on his mind in London, though. Clement finished third at the U.S. Olympic trials behind Taylor and first-place finisher Michael Tinsley, so simply earning a medal won't be easy. His London experience certainly didn't get off to a great start. The bus Clement was taking to get from Heathrow Airport to the Olympic village was lost for four hours, leading Clement to tweet "Not a good first impression London." After his days on the track are through, Clement might have a second career to fall back on. He's a model and actor who appeared in Beyonce's 2011 "Run the World (Girls)" video.