I was reading How can I humidify a room without a humidifier?, and it got me curious.
I live in Florida where the humidity is insane. Dehumidifiers cost hundreds of dollars. What is a cheaper alternative to dehumidify a small room (about 10x10)?
An ordinary air conditioner dehumidifies the air as it cools. If you don't need cooling, you can let the machine's hot air exhaust mix with the cold, and you'll get a slight heating effect, but the water will still be pulled out of the air by condensation on the cold evaporator coils.
You can get small air conditioners for under $100, though you might have to improvise a bit in terms of mounting to use it this way.
You can get a portable dehumidifier. It doesn't cost that much. I have one and it works well for a single room. The one I got is this Ivation dehumidifier from Amazon
Turning on AC in the summer and turning on furnace(electric heater) in the winter also helps reduce humidity in the room.