I've been using the humidifier in the colder months on recommendation from my allergist (going on my second year). It really helps keep my throat and skin from getting dried out in the middle of the night. Before I tried the humidifer I'd bought a vaporizer from Wal-Mart for $9. It worked okay but I like my humidifier better because it has a mist control knob (low, medium, and high) where you can adjust the amount of mist going into the room and the humidifier seems more effective.
The downside to the humidifier is that its noisy (I have the Robitussin brand), you have to refill it with water every couple of days, plus you have to disinfect it once per week to keep it bacteria free. I usually just start it out on high for an hour and then turn it down on low when I go to bed and turn it off when I get up the next morning.
Hope this helps!