When a pair of galoshes is the year's best purchase, it could be argued that 2011 was a pretty lousy year for gear. Either that or Swims' "Mobster Boot" Overshoes are that good.
Whether you wear Chuck Ts or wing Ts to work, these protect them from rain, snow, sleet, (and even hail!), keep your feet warm, and they pair as nicely with a pair of denim as pair of wool trousers. They even have a reflective square on the heel for inclement cycling, which is what we've adopted them for. $149 is not cheap for something that may cost more than the shoes you're trying to protect, but they're totally worth it.