+1 This is standard for me. I leave a pair of shoes at work and transport everything else. Desenex anti-bacterial spray keeps odor possibilities at bay. My work enviornment is office causual/warehouse, so it's not as much of an issue as one who works in a more formal situation.

During cold/inclimate weather I use Lake winter cycling boots w/2 pair of socks. One thin and one 100% wool knee high. Shoe cover options consist of Bellweather, Performance, Look and Nashbar. They're used in combination w/different shoe/sock configurations depending on the type of weather. The main thing if using cycling shoes w/covers is to remember to not use shoes w/mesh insteps as it defeats the purpose of the shoe covers.

It doesn't snow that much here in TN, but if I still lived in Chicago I'd have a rig set up w/Power Grips and low psi wide studded tires, that's for sure. Rubber, wool lined boots and waterproof pants w/elastic cuffs and gaiters, too. Started my cycle-commuting career in the Windy in the beginning of February, so my learning curve was steep. I was on a 3d hand road bike and thought falling down in the slush was just part of the drill.