The December edition of Digit Magazine (a shiny bouncy design publication with thick pages and few words) is giving away Bryce 4.0 in the pack-in CD. Yeah, I know its a couple of months old, but it takes a couple of months for things to cross the pond. My local Micro Center had plenty of 'em.
For the uninitiated, Bryce was the only (to my knowledge) standalone tool that came from the development team that made the very cool Kai's Power Tools plugin suite. It's rather a weird bird. It's a very rudimentary 3D modeler with beautiful landscape-generating capabilities. It's also got an oddball user interface that later migrated to Carrara and Poser before Metacreations made the brilliant decision to sell their product line in an attempt to become irrelevent as quickly as possible.
Anyway, if you want some kind of background landscape in your program, check it out. For $13.95, it's worth a look.