MikeMax has created this rather fun driving demonstration on the PSP, which is actually the beta release of his car's 3D engine. It's called the Vertex 3D Car Demo Beta, and it's definitely well made.

Here are MikeMax's directions for installing the demo and the commands for driving the car and manipulating the camera:

Simply unpack the zip archive to your MSROOT (FW1.50) (will unpack into /PSP/GAME automatically).

For 3.xxOE, next, move the Vertex Origin directories into /PSP/GAME150 (only if your OE kernel configured to 3.XX).

Commands:

o Cross: Accelerate
o Square: Breaks
o Digital Pad: LEFT/RIGHT to turn, DOWN for reverse.
o Analog Pad: Move camera
o Circle: Display wireframes
o SELECT: Switch between two camera modes : "Free" mode and "follows car" mode.
o L/R: Zoom

Now MikeMax is also looking for additional volunteers to help him work on improving the engine by getting someone to improve upon the models and textures for the car. Send him a message on our forums if you think you can help.

As for getting the most out of the driving sim, Here's a funny thought: mute your PSP, make car sounds, and turn in the direction your in-game car is turning, just like Hiro Nakamura from "Heroes." Enjoy!