3d level editor

Does anybody know of a good terrain/world editor besides Halflife’s and the standard Quake ones? I’d like to find one that can import heightmaps and position basic models, and maybe also handle terrain texture blending. I’ll write my own if I have to.

I haven’t used this in a long long time, but somewhere out there, there is a program called Gmax. It is a second FREE version of 3d studio max R4, but made for games. (So it can do almost everything except render scenes, but it can import models, create landscape noise, etc)

Here is the adress (you will have to register with their sight, but its free)
"Discreets" Gmax