My cold-prevention system is simple: Wash hands often and use alcohol-based hand sanitizer if I can't wash. I have a small bottle in my purse and a huge one in my car, which I use after pumping gas, going into any stores, on my way home from work...) Okay, so I may sound like a germaphobe , but it's well worth being a little neurotic to me. I am around sick people all the time at work (why oh why won't folks take a day or two off when they are actively ill?!) and have managed not to get a cold of any sort in ~2 years (only "sick" day I took in 2008 was for dental work, and in 2007 my one sick day was due to a bad reaction to my flu shot).

For me too, I think the fact that I am almost never around kids helps. Co-workers who are parents of young children seem to get a cold every couple of months.

Good luck -- being sick is no fun indeed (I think I remember that, anyway!)