Check out some of Christian's designs... if anyone can find some more info and provide to us, please do (English translations welcome, too).
NXTOffRoad at Workhttp://www.mindstormsforum.de/bilder/details.php?image_id=138&sid=2ae1c901bfebaff175e1d[url]9a73e9e5d0b
NXTOffRoad Build-0http://www.mindstormsforum.de/bilder/details.php?image_id=140&sid=2ae1c901bfebaff175e1d9a73e9e5d0b
NXTOffRoad Build-1http://www.mindstormsforum.de/bilder/details.php?image_id=139&sid=2ae1c901bfebaff175e1d9a73e9e5d0b
Developerversion with MCUhttp://www.mindstormsforum.de/bilder/details.php?image_id=141&sid=2ae1c901bfebaff175e1d9a73e9e5d0b
Cableconverter for extensions (MCU-Board for SD-Card, Camera, Motors andadditional IO-Ports)http://www.mindstormsforum.de/bilder/details.php?image_id=142&sid=2ae1c901bfebaff175e1d9a73e9e5d0b
NXTOffRoad at Workhttp://www.mindstormsforum.de/bilder/details.php?image_id=138&sid=2ae1c901bfebaff175e1d[url]9a73e9e5d0b
NXTOffRoad Build-0http://www.mindstormsforum.de/bilder/details.php?image_id=140&sid=2ae1c901bfebaff175e1d9a73e9e5d0b
NXTOffRoad Build-1http://www.mindstormsforum.de/bilder/details.php?image_id=139&sid=2ae1c901bfebaff175e1d9a73e9e5d0b
Developerversion with MCUhttp://www.mindstormsforum.de/bilder/details.php?image_id=141&sid=2ae1c901bfebaff175e1d9a73e9e5d0b
Cableconverter for extensions (MCU-Board for SD-Card, Camera, Motors andadditional IO-Ports)http://www.mindstormsforum.de/bilder/details.php?image_id=142&sid=2ae1c901bfebaff175e1d9a73e9e5d0b