England's last Grand Slam in the Six Nations was in 2003.
This year, 2008!
Ireland ( 2008 / 2009) Six nations Tennis: The last to win the singles Grand Slam was Steffi Graf - during the 1980's
Technically the ATP season ends some time after the U.S. Open so it is the last Grand Slam Tournament played, but in the next season the Australian Open is the next Grand Slam tournament played after the US Open.
In MLB, that is Julio Franco of the Atlanta Braves. Franco hit a grand slam off of Valerio de los Santos of the Florida Marlins on June 27, 2005 at the age of 46.