The FS Weekend event is the largest flight simulator event in the world. Each year it takes place at the first or second weekend of November. The event is held in the Aviodrome musuem, located at Lelystad Airport, The Netherlands. Since 2006 FlightGear has been represented each year, by a small team of enthusiastics. If you like to join the team, write an email to the mailinglist.
Keep an eye on the current events to see what dates this years event will take place.