This works great for NiMH batteries. They'll retain 9/10 of a full charge while stored in the fridge. At room temperature, there is a possibility that they'd keep only a fraction of that fraction. Alkaline batteries are a bit more controversial. Studies have shown that alkaline battery life is extended by only 5% if kept in the fridge. That's not a whole lot, but if you live in a hot climate, your batteries may actually deplete because of it, making the alkaline-battery-in-the-fridge idea a worthwhile one. If you live in Alaska, your batteries are probably all right sitting in a drawer in the pantry.
NOTE: Make sure to warm up batteries to room temperature before using. Additional, if you need batteries for an emergency, remember to keep a set out of the fridge for just such emergencies.
For more tips and information about batteries, see the next page.