I have used Cold-Eeze but it dried out my mouth and made my tongue sore. What I like better is Zicam. They make swabs that you wipe inside your nose (gross, but it works).
This works for me. It does dry out the inside of your nose, but at least my tongue doesn't go raw sucking on zinc! If I start this at the beginning of my cold, I find that my cold rarely develops into something full-blown. I guess it's predicated on the idea that the cold virus replicates in your nose. Use it exactly as directed to work (e.g., you can't blow your nose for 30 seconds after you use it).
Zicam also makes a mist that you spray inside your mouth, but it gives me the same icky feeling of sucking on zinc tabs.
Good luck and stay healthy!