Game controllers, kids’ toys, digital cameras, and other electronics chew through batteries faster than beavers chew through balsa wood. Consequently, they chew through your wallet as well: A four-pack of Duracell AA batteries sells for around $6. Buy just one pack per month and you’re out $72 a year.

Or you could invest about $25 on an Energizer four-slot battery charger (which comes with a pair of rechargeable AAs) and a four-pack of extra rechargeables. Sure, you’ll pay for the electricity to recharge them, but compared with disposable batteries, outlet electricity costs pennies on the dollar–and new disposables, remember, are destined for landfills.