My good friend Josh Slack over at Ardor3D has been working on a little project in his spare time to show off the features and performance of his Ardor3D engine. In a video series called "Ardor3D - L4D 'hobby project'", Josh starts detailing the process of importing Left4Dead maps into the Ardor3D engine. Josh has an excellent speaking manner that helps to simplify the explanation and is presented in a very straightforward way.
Check out Episode 2 here:
Now, I would be remiss if I did not also point out that the Ardor3D engine is a JAVA engine. Java and performance? Yep. Again.