Go to any Hydro Store and ask for the Oregon temp\humidity gage. I have the remote access one... it's Wireless so I just throw the gage in the room, and I can view my humidity and temps while I'm sitting on the couch smoking a joint. It's nice. =)

Costs about $50, well worth it. It really makes all the different in the world when you don't have to constantly go into the room to see whats going on.