Hattrick (also known internally simply as HT) is an online, browser-based, football management game. Over 860'000 (!) users are managing their team in 112 Countries, using 36 different language versions. The Solution is ASP-based, developed and maintained by 14 employees from the swedish company ExtraLives AB.
Interested in more information? http://en.wikipedia.org/wiki/Hattrick