I haven't found a cure for the cold, but here is what I do to shorten it.
As soon as I feel sick I take 3000mg of vitamin C. Then I take zinc losenges like Cold-eeze or a generic brand. I continue that day taking 1000mg of vitamin C three more times, and the zinc as recommended as well. The next day I also take 1000mg of vitamin C 4 times that day and continue with the zinc. I also avoid candy and sugar because sugar decreases the immune system. I am a big believer in green tea with honey (the only sugar I allow myself).
I also take a look at my life and see if there has been any unusual stress. Stress=getting sick.
The last time I got a cold I did this and it only lasted 2 days.
When you're not sick I recommend Emergen-C. You get it in packets at Target or the grocery store and mix it with water. Take at least one to two a day, that will boost your immune system! I also love Emergen-C because I take it to restaurants and mix it with the free glasses of water. You don't have to buy a drink and you know you're getting your vitamins along with a tasty (free!) drink! I love the pink lemonade flavor!