Shopping cart slide
When in online multi-player mode, find a shopping cart. Make sure you have someone with you. In multi-player mode, everyone has their own shopping cart, meaning that the shopping cart on your screen is invisible to everybody else. Run into the shopping cart and make sure it moves. While it is moving, try to jump on it. If done correctly, your character will appear as if he is drunk or stumbling everywhere, but on your friend's screen, it will appear as if you are sliding on the ground. Sometimes you will slide/stumble longer than others. You can do this in Story mode, but you will only stumble.