Nothing but a traffic violation.
I don't even want to waste your time with this one, so let's do this efficiently. I'm going to go through some absolutely terrible things about Asphalt 2 and you just stop reading when you're convinced you're not going to buy it. I mean it. Go spend the time doing whatever it is people do when they're not playing video games. Go take your shopping for a walk, or water your granddad or something. In this small way Asphalt 2 will take up a bit less of your life and we can both feel victorious.
Let's start big. This is a port of a mobile phone racing game. Not even a 3D racing game, it's a port of one of those ones where you're stuck facing forward and you follow a streaming 2D road. They've given the game a 3D engine for the PSP and DS versions but it looks absolutely hideous and the origins of the game are hinted at by little things like an agonizingly slow turning circle and an inability to reverse. Boy, it's a glorious moment when you first find out about the reversing. Desperately slapping all the buttons on your handheld with your car scraping against a wall and all of your opponents overtaking you.
One thing you can do is nitro boosts. These draw from an onscreen meter that you can refill by driving into massive blue markers that float above the road. However using nitro has the same effect as taking down the competition by forcing them into walls, buzzing civilian cars and other things bootlegged wholesale from the Burnout series. But instead of being rewarded for these things, you're punished - in addition to netting you a bit of cash they also fill up your Wanted meter. When that gets high enough, police cruisers start buzzing you and helicopters start pointing laser pens at you. Eventually you'll realise the laser pens represent machine gun fire but the game's engine is so completely inadequate this takes you a while. Being pursued isn't too much of a problem since you're near indestructible but it is extremely irritating to be coming up to the final straight with half of the city's police force crawling up your jacksie while your AI competition gets a free pass.