Medieval Playground is an interactive medieval setting with a first-person perspective and realistic physics. I developed this application for a virtual reality class taught by Dr. Carolina Cruz-Neira. It was my first real application that used ODE for physics simulation. Thanks to Matt Newcomb for writing the particle system code.
In Medieval Playground you can explore the world and interact with it physically. Climb on the castle ruins. Pick up a loose board on the bridge and drop it into the water below. Pile loose objects on the catapult and launch them at the castle... even launch yourself if you want. Swim along the water surface with the floating debris. Dive underwater to see fish schools (using a physics-based variant of the boids flocking algorithm). Even grab a fish and carry it away, forcing the rest of the school to follow you. Download it and try it out!