Ski goggles are a good option, but the main problem with ski goggles is that they block your peripheral vision, even if you have clear lenses. You should augment them with a helmet mounted mirror. These work well with balaclavas (which are nice in the winter, depending on where you live).
Regular old clear safety glasses like you use in high school chemistry such as the 3M 91252-80025T are another good option especially if you wear glasses. They don't impair your peripheral vision, but they do leave an imprint under your eyes due to the band tension. Sometimes you have problems with the nose area if you're wearing a balaclava. There are a bit more stylish ones like the Uvex Ignite series, but those don't work well for people who wear glasses (You may want something bigger than these in area as well, but in the same style). These are similar in style to the cycling glasses Fox and other companies sell, but cost a fraction of the price. I've found in general safety glasses to fog less than ski goggles at the tradeoff of slightly less isolation. At -30C, I'd probably be inclined to use the ski goggles, especially if there was significant wind.
You may also want to consider a full face cycling helmet with visor but these have the most severe peripheral vision penalties and you may get hot. Mirrors are a must with this.
Note that you may want tinted lenses at times as well as clear lenses due to the same reasons as skiers (glare, etc.).
As for fogging, you can try things like cat crap, depending your lens material.