OK, it's not quite a flight simulator, but Mark Caswell-Davis has built a fun "Flash 8 Google Maps" flight simulator called Goggles Flight Sim. It is really interesting to think about this as a simulation mash-up. Imagine instead of map data if a Flash movie used a business model or other data from a web site/service. One could quickly and simply make some pretty powerful training.

Before you head off and try Goggles, note that

I had a lot of fun with this today. If you want to create your own start locations, it is easy to follow the author's instructions for linking to your own Goggles starting point using Google Maps and Firefox.

Without sounding too much like Elliott, I really think this could be a new model of creating training simulations; lightweight integration into existing services using a UI, some minimal instructional information and a scenario to launch learners into an experience they control and that has inherent consequential feedback from their actions and the response of the model. Note the lack of instructions needed for this example and the effective cost.