This multiplayer action game combines first person shooter with semi-free flight. The main goal is to create a fast-paced action/arcade game which is fun to play and addictive.
Below are a few screenshots of the concept demo while developing.
Initial skybox and model rendering 
Menu support 
Some actual ground plane vertices 
Transparency support 
Follow camera 
First attempt at a height map. Vertices did not connect. 
Cube map reflection support. 
Height maps working 
Some better camera support 
Actually got someone with art skills to draw the UI. (Thanks Pieter!) 
Debugging detail textures 
More details look better 
More controls – barrel (aileron) rolls and other maneuvers 
Projectile weapons. 
More particles 
Collision detection 
More camera improvements 
Crash animations 
Maneuvers are executed through mouse gestures. 
Level 2 – more rocky. 
Attempt at some 3d menus 
Putting it all together.
TwyFlight has not reached any playable phase yet, but there is a concept demo of TwyFlight available for download.