[Algorithms] 2D Side Terrain generation

[Joel B <one...@ea...>]

Hello, I'm looking for algorithms for generating 2d terrain from a side view, like the old Defender game from the 80's, except with mountains grass, rocks, lakes etc instead of just lines.

Here is an example of what I have done in Photoshop:

http://img855.imageshack.us/img855/8125/examplelp.png

Anyone on this list have some suggestions? It doesn't have to be real time, although that would be interesting too. 

 - Joel