If it?s not there already, I haven?t got 2008 yet, I would like to have collision detection when moving with the flythrough/walkthrough tool, so that the viewpoint follows the terrain when decending to a set height, say 1,6 m when walking, say 1,2 m when driving. The function could be applied to selected objects, say always to the terrain model, to walls and floors if you don?t want to walk through them, but not to doors.