I have been playing TORCS and Speed Dreams lately. It was not too long ago that Speed Dreams came out with version 2.2.0. What compels me about these games (especially TORCS) is that there are people who utilize the game to set up robot/AI racing. I've seen YouTube videos of people using certain logic formats to control cars. The AI can be laughable at times, but these are fairly good AI racing games.
I am not sure whether I like TORCS or Speed Dreams more in terms of structure. TORCS runs faster with the simple models and the simple textures, and I also realize it has sort of a team format. Only other game that kind of has a a little team format to it that I remember playing was the old "Car and Driver: Grand Tour Racing '98." If any of you ever played this game (also known as Max Driving or Total Driving), every team had five cars to take on five different racing disciplines. Kind of the same way with TORCS. Most of the different teams have a handful of cars. I almost feel like wanting to make my own fantasy racing team- Moonlight Motorsports into this game.
On the other hand, Speed Dreams seems better sorted as you're able to properly choose between the different categories. Also, you can tell drivers by name rather than by team name or something. The AI is a bit less weird in Speed Dreams than in TORCS. The car models and such are better looking in Speed Dreams, but things run just a bit slower. Besides cars, I could see putting together a fairly decent race track and have it be raced on by any team. The amount of detail doesn't have to be like any modern racing sim, but I can surely see making at least fairly decent courses to race on for Speed Dreams. Just for fun, one of the tracks in the latest build of Speed Dreams is called "Milky Five," based on the Indianapolis Motor Speedway oval, and I realized rather late what the connection is. Of course... whomever wins the Indy 500 drinks milk in Victory Lane. You have to love the creativity of certain names and such when you can't get officially-licensed material!
Either way, I am enjoying both games. I am playing both titles mostly to look at trying to maximize making models and even maybe starting some kind of fantasy racing championship (much like TIRE, RACE, and all of the other series here on GTPlanet).