Feudalism is another one of those concepts that can be entertainingly and deliciously demonstrated in a classroom setting by having students play the roles of the different social stations in the pyramid and making candy representative of the rights and obligations due between lords and vassals. The teacher provides a running narrative of how feudalism works throughout this activity, making it a very interactive lecture.
Many of my students do MUN; I myself attended the IASAS MUN Conference in 2000 as the Russian delegate. This simulation is inspired by such negotiation- and speech-based events. Students are divided into groups and essentially debate the relative merits of the respective civilizations.