NFL:
Tom Brady - Drafted by Montreal Expos before attending college at the University of Michigan
John Elway - played minor league baseball for the New York Yankees and the Kansas City Royals
Antonio Gates - was an all-conference player in college basketball at Eastern Michigan and Kent State.
Dan Marino - was drafted by the Major League Baseball Kansas City Royals.
Donovan McNabb - Played basketball for Syracuse University.
Terrell Owens - While at the University of Tennessee at Chattanooga, also ran track. Also played basketball in college, the Sacramento Kings summer league, USBL's Adirondack Wildcats.
Tony Romo - Is an avid golfer and attempted to make the U.S. Open in 2005 and 2010.
Maurice Jones-Drew - ran track at UCLA
Michael Vick - Drafted by the Colorado Rockies in the 2000 MLB Draft
Ricky Williams - played four years of minor league baseball
Julius Peppers - While at the University of North Carolina, Peppers was also a walk-on member of the men's basketball team
Stephen Neal - Was an olympic wrestler in 2000
MLB:
Carl Crawford - was offered scholarships to play American football and basketball
Jackie Robinson - played professional football in the PCPFL, and ran track at UCLA.
Dave Winfield - was drafted by four professional teams in three different sports - basketball, baseball and American football, before deciding to concentrate on his baseball career
Joe Mauer - Played quarterback, point guard, and catcher in high school, and was named USA Today High School Player of the Year, twice: in 2000 for football and 2001 for baseball.
Bo Jackson - won the Heisman Trophy, and was an all-pro in the National Football League and also played on a semi-pro basketball team in Los Angeles before returning to baseball
NBA:
LeBron James - was an all-state high school wide receiver.
Michael Jordan - briefly played as an outfielder in Class A team for the Chicago White Sox after his first "retirement" from the NBA
Wilt Chamberlain - Played volleyball in the IVA for the Seattle Smashers 1974-1979.
Allen Iverson - standout quarterback in high school