This post is as a follow up to the previous post.
I have greatly been interested in fractals and have played around with models and mathematics of the same. With a friend of mine i have developed many NetLogo models as well.
The NetLogo website offers very decent models of fractals. These can be run for the curves.
The models allows the user to change parameters and see the change. NetLogo models such systems amazingly!
1. Koch Curves
You could play around with these models to get a good understanding of L-system generation. These models can also be extended if they really fire you up!
Related Post: NetLogo Version 4.0.2 released