Once upon a time, the only way to gain any meaningful increase in winter tire traction was to either purchase a set of studded winter tires which are illegal in many states, or to carry around a set of heavy and inconvenient tire chains. Fortunately, the relentless march of technology has brought to us a number of viable alternatives that offer most of the traction of chains, but are quieter, less damaging to the road and easier to install.
Modern tire wraps like the Autosock don't seem like they should work, but they do if used properly. Tire wraps are fishnet-like "socks" that are slipped over the tire from the front, covering the tire tread and hub-cap area. While very light, quick and easy to install, tire wraps will tear and wear out very quickly if driven over a dry road surface. They are, however, legal in all 50 states and work well with stock ABS and stability control systems. The grip is a little better than with a dedicated winter tire like the Bridgestone Blizzak. Autosocks cost about $75 for a set of four and work well for most applications.
One of the more tried-and-true alternatives to chains are tire straps like the Go Claws. These should be considered as the next step up from mesh tire wraps, and offer good snow and ice grip with good dry road wear and quiet operation. Go Claws says that they've driven their product on hot dry roads for over 200 miles without significant damage or wear.
Tire straps are easy to install, and can be put into place without need to reposition the vehicle. To install them, you only need to wrap the straps around your tire, and fasten the retaining straps that run in front of and behind the wheel. The whole procedure shouldn't take more than a minute per wheel. Tire straps are available for commercial vehicles, and cost about the same per wheel as an average winter tire. Many tire strap systems are sold as "plastic" or "non-metallic snow chains."
If mesh tire wraps and straps don't work, then you're going to need to step up to something a little more aggressive. Tire boots have been around for decades in countries like Norway, Sweden and Russia and are essentially a set of removable tire treads. Think of your regular tire as a bare foot, and these devices as a kind of shoe.
One of the more popular brands of tire boot are SnoBootz, which have a very aggressive tread pattern and work well for deep snow. Tire boots must be driven over to install, but they wrap very tightly around the wheel and don't have the suspension-clearance issues of tire chains. While quite expensive--around $300 a piece--snow boots will give you the best traction this side of studded tires or heavy chains.
