@Feryll - Try buying some of the small closet dehumidifiers. You can buy the small ones that simply sit on a shelf or on the floor, or you can buy the ones that are bags attached to hangers, and you can hang them like you hang a shirt or a pair of pants. These dehumidifiers have little balls or pellets that absorb moisture. The moisture then collects in the bottom of the container.
I like these because I can see just how much moisture they are removing from the air as the water collects in the container. And using them is much simpler than using an electric dehumidifier, and removing the moisture is much simpler than removing mildew or mold from your clothing.