Hey
I've been looking into this too, and there are a few memory offset values I've found with other programs which indicate the value of NOS and turbo's etc... CheatEngine is a pretty good program for reading memory locations in game. I know some people use it for making trainers, but the interesting part is, it's pretty good at finding memory to read and display information.
I believe RacerS uses something like this for making his FOV and headtracking applications.
I'm building some custom LED buttons into my setup and lighting up the buttons when a weapon, power up, or simple NOS is ready to go would be a fantastic use of the spare LED pins I have available.
Thanks
Ramjet