In a very scientific study conducted by Dr. Me, in a test group of 'a bunch of my friends,' I've found that every person on the planet falls into one of two categories: Those who throw out batteries as soon as they wear out the device they were in, and those who save possibly partly-charged batteries in a messy kitchen drawer.
Both ways are generally wasteful because its safe to say in both cases that the batteries will never be heard from again.
Get your battery drawer in order with this tip from Lifehacker: Buy a cheap multimeter (You can find some for less than $15) and test every random battery lying around your house.
Any batteries that read less than 1.2V, discard for recycling. Any that read between 1.2V and 1.4V are partly charged and great for use in a small clock or other small-power device. Any batteries that read above 1.4V are fully charged and can be used in nearly anything for a decent while.
The really tricky part—listen closely—is keeping them organized like this. Lifehacker's reader suggests using double-stick tape to keep the batteries stuck to a labeled card. Or you could go the lazy route and stick 'em in sandwich baggies inked with permanent marker.
Before you know it, you'll be saving money on batteries and—bonus!—you'll get your junk drawer back. For more important things. Like nightlights, rubberbands and take-out menus.
(Image: Flickr user awnisALAN under license from Creative Commons.)
Must-See Small Cool Homes: Week Two
Beth's Romantic & Retro Residence
Good Food to Share 
The Big Book of Small, Cool Spaces 
Apartment Therapy Presents 
The Eight-Step Home Cure 
Commercial Flour Sa...
How to Bake a Potato: Three Easy Methods
How To Cook Tender, Chewy Wheat Berries on the Stovetop
....or you could just use the $15 to get a rechargeable battery kit. You can actually find really good ones at Marshall's, TJ MAXX, etc.
Hah, I came into say the same thing Miss Upsetter.
If you're still using non rechargable batteries, swapping them into other electronics may be less wastefull, but you're still being wasteful. Just buy some decent NiCd rechargables! They pay for themselves quickly.
Great tip, I have a few used batteries in my junk drawer. I've been meaning to recycle them, but it just never happens. Time to break out the multimeter!
Rechargeable batteries is fine I guess, but how do you make sure you always have some fresh batteries ready when you actually need them? That is what has been keeping me from using them.
If you've ever bought batteries in quantity from, say, Home Depot, the larger packs (24 or so) come with a plastic tray that is great to repurpose as an organizer for your battery drawer.
also the Second Wind charger http://www.apartmenttherapy.com/secondwind-charger-lets-you-recharge-non-rechargable-aa-and-aaa-batteries-169061