A virus is a microscopic organism that can replicate only inside the cells of a host organism. Most viruses are so tiny they are only observable with at least a conventional optical microscope.
Recognized by the Guiness Book of World Records as the MMO with the longest play time per player, and easily the oldest game on this list (launching four years ahead of World of Warcraft, way back in 2001), Runescape deserves mention because it's one of the most updated and popular games of any kind on the planet.
Mamma Mia! played in Las Vegas, opening at the Mandalay Bay in February 2003 and closing on January 4, 2009. In June 2005, Mamma Mia! played its 1000th performance in Las Vegas, becoming the longest-running West End/Broadway musical in Las Vegas. The clothes and scenarios from this production are now used in Brazil.amma Mia! played in Las Vegas, opening at the Mandalay Bay in February 2003 and closing on January 4, 2009. In June 2005, Mamma Mia! played its 1000th performance in Las Vegas, becoming the longest-running West End/Broadway musical in Las Vegas. The clothes and scenarios from this production are now used in Brazil.