If you are keen on Mission Possible but plan to invite participants to a venue for a meeting, you should consider Plus Agency's product, Fairground. It is developed to focus on involving all participants and encourage sharing of knowledge. Would you like it to have a competitive element as well? We can make that happen too.
In Fairground participants are divided into small groups, moving around to a series of stations and solving different tasks. Each group has full autonomy and no timing restraints: When you have finished a task at one station, you promptly move on to the next. Typically, groups spend between 10 and 20 minutes at each station.
The activities encourage participants to enter into professional dialogue and share knowledge, and just as Mission Possible, the focus is on play and learning. We have developed a platform to track the participant's journey through the many stations, ensuring that they move on to new stations with a format and an objective different from the one, they just left. 500 participants will require approximately 90 stations with a variety of activities (some are the same!), so everybody is kept busy and have something new and exciting as their next task. Plus Agency received the Danish Meeting Planners Association's Oscar for this concept -
see the case here