At least in the city (downtown), they salt the streets and sidewalks to prevent too much slipping. This doesn't mean that ice is non-existent, and I'm pretty paranoid about falling on my butt on those tiny patches (it usually gathers wherever there would be a little puddle, and right off the edge of the curb so if you're not looking when you step into the street, you might slide onto your butt). Lately, the weather has been very odd--warm and humid, raining, and then freezing cold and snowing. These varied conditions created a good amount of ice! Enter: Lifehacker. This infographic was pretty useful to me (though the comments on the page said otherwise). I haven't put it to the test yet, but I'm going to keep it in mind.
Additionally, a few other people have recommended Yaktrax to me. I don't personally own them, but these recs come from reputable sources, so I would trust them. I have a couple pairs of snowboots I usually wear when it's icy or snowing to avoid slipping, but they still slide around a little bit. Everyone stylish and hip here swears by Hunters. I have a pair, but I did slide a little on the ice. They aren't entirely accident-proof, but they are stylish. Mine are purple--most people have black and other subdued colors. Eh, who wants to wear black all winter?! Those boots are great for keeping your feet dry, but I do recommend getting the fleece liners to keep them warm: Hunters alone are not enough, even with wool socks!
What are your tried and true tricks for not falling on the ice?