TerrainGen

[Entar]

http://entar.quakedev.com/wiki/index.php/TerrainGen

[Monster]

Interesting. You might be able to make some RocketArena maps with that. Like terrain2

[scar3crow]

Or you could use it to make some nice detailing to a sp map for background things - or just put some rolling terrain between your outcropping of rocks and that despotic castle in the distance, and use some dramatic lighting (like a sun light point) to frame it and make it all the seemingly bigger.

True, quick RA maps can be made, but this can also be useful for much better looking maps in general.