The Unfolding Story of The Engine That's Behind Your Web Browser
Ars Technica has an excellent write-up about the evolution of KHTML, an open-source web browser layout engine.
The story is fascinating as it talks about the forking of the project which is a normal occurrence in the open source world.
Also revealed is the tumultuous relationship between the open source community and the big software companies, in this case Apple who forked HTML to build WebKit (used in Itunes, Safari) and Nokia who forked WebKit for its smart-phones.
The most interesting bit in the article to me is the unforking of the above projects which is a rare event and usually means good things for the developers who can be confused between what to choose as both platform are related but different.