One of the most popular simulation game, SimCity has published their source code for public. People can start working on the porting to other platform and other programming languages, but for now, a new project has been started by Don Hopkins (Micropolis). The project name is renamed because EA wanted to protect their trademarks.
There's been changes to the original system like a new splash screen, some UI feedback from QA, etc. The plane crash disaster has been removed as a result of 9/11. What is initially released under GPL is the Linux version based on TCL/Tk, adapted for the OLPC (but not yet natively ported to the Sugar user interface and Python), which will also run on any Linux/X11 platform.
The "MicropolisCore" project includes the latest Micropolis (SimCity) source code, cleaned up and recast into C++ classes, integrated into Python, using the wonderful SWIG interface generator tool. It also includes a Cairo based TileEngine, and a cellular automata machine CellEngine, which are independent but can be plugged together, so the tile engine can display cellular automata cells as well as SimCity tiles, or any other application's tiles.
If you want to port it, grab the source and start porting it.
Source: ASP.NET Blogs