Terragen
Terragen is a popular, high-quality freeware Microsoft Windows and Apple Macintosh program for generating pictures and animations of landscapes.
It is popular among amateur artists, which can be attributed to it being freeware, its intuitive interface, and its capability to create photorealistic lanscapes when used skillfully.
A commercial version of the software is also available and is capable of creating images with higher resolution than the freeware version. A Terragen image appeared on the April 16, 2001 cover of Newsweek, and Terragen was used for animations in Brandy Norwood's "What About Us?" music video.
Terragen can also be used to create skyboxes for 3D video games.