ManiaDrive is an open-source clone of the popular racing game TrackMania, with support for online racing and extremely realistic physics.
I must say I haven't tried TrackMania so I can't compare, but the overall impression I got from ManiaDrive is just excellent. People often tend to think that free games can't be high-quality products, but ManiaDrive is a fun game with tutorial sessions, quick races, online competitions a highly realistic physics.
This degree of realism is precisely what makes the car quite difficult to control, especially at the beginning. But I'm sure most players will love the driving sensation provided by ManiaDrive and based on the game's philosophy, where completing a clean race is as important as being the fastest pilot.
Mania Drive includes a series of training races that are used a tutorial to teach you the basics of the game. After that, you'll be ready to start your own championship in Story mode or compete online against other players. I did miss, however, having the chance of disputing single races.
A fun, free racing game with support for online competition that requires great ability due to its realistic physics.