SilverStone Raven RV01
To illustrate why the motherboard tray is rotated 90 degrees on the Raven RV01, there are two videos compliments of SilverStone Technology. Both videos are short and designed to illustrate the "stack effect" cooling with this chassis.
The second video shows a completely fanless system based around the SilverStone Raven RV01 even when using an ATI Radeon HD 4850 and Intel Core i7 920 processor.