When we moved into our previous apartment one of its biggest perks was a basement where we could shove our seasonal clothes, photos that still needed to be put into books, and unused electronics that were waiting for Craigslist or the local e-cycler. The big drawback of this perk revealed itself after six months -- mold!
After an especially brutal and humid New York summer, knits were covered with the plush, but not so healthy, stuff along with an old computer monitor and speaker stands. A friend in New Jersey had a similar problem, but in her case, something much more tragic happened -- a large majority of her archived photos were damaged.
For any of you who also battle harmful humidity in your home's subterranean rooms, may we suggest Sensaphone WSR-0103 Wireless Humidity Sensor. This white plastic sensor can be placed in any room in your home and will monitor the humidity in that room. It will alert the home base up to 100 feet away, if things are getting sticky icky.