Interesting video of Fallingwater in Bear Run, Pennsylvania that was produced using the Half Life 2 Source gaming engine. The Google Sketchup version can be found here. Needless to say, these three dimensional models would seem to be highly pragmatic devices for teaching Architecture in primary, secondary and post-secondary school environments. Something that is lost when viewing either pictures or slides in an academic presentation and can not be viewed first hand due to budget and/or time constraints in one's academic schedule.
Digital Urban Link
Official Fallingwater Site