This modification allows you to control your GTA Singleplayer with scripting.
It implements a PAWN virtual machine into your game and allows you to run .AMX scripts and .DLL files.

Good alternative for Cleo, just, not (yet) as feature rich.

Here are some videos of what can be made with it:

http://www.youtube.com/watch?v=3UvHcFj-g4Q
http://www.youtube.com/watch?v=5gpKNRq4LAI
http://www.youtube.com/watch?v=Ycf5coAmmMA