Photographers use silica gel as a desiccant for long term storage of cameras. The lowered humidity helps prevent fungus growth on camera lenses (which goes to show life grows everywhere).

I have heaps of silica gel at home in airtight containers with my old cameras. Every now and then, I go recharge them by placing them in an oven or, if I'm really lazy, the microwave. They go from pink to blue when the beads are ready to be reused.