We all have a nifty bit of decoration or electronics that we’d use more often if it didn’t eat batteries like a Mormon teen devouring Cheetos after a date.
A device called a “battery eliminator” allows you to run a device using a power supply, even if it was designed to only operate with batteries.
A battery eliminator works by connecting a fake battery to a power supply, via a thin cord that snakes out through the battery door. This one battery carries all the necessary juice to run the item, but you need to fill the other battery slots with dummy batteries that complete the item’s circuit.
Simple, and it works great, so long as you don’t mind tethering the item to a wall wart. (And, duh, if you do mind, just go back to using regular batteries!)
The only obstacle to using a batter eliminator, from my perspective, is the cost. You also have to buy one that meets the specifications of the device you want to power, so it may not be possible to use the eliminator with other devices that you own. That is, the eliminator has to match both the power, and the battery size, the device requires. (Such as, 3v and AAA batteries.)
A slightly more flexible (but costlier) version of an eliminator is one that lets you switch between different voltage output. That’s what I use, but note that it’s still tied to replacing AA-sized batteries. Visit the listing for the Lenick Adjustable Battery Replacer on Amazon, and it will lead you to all the other available configurations. (I just noticed a bring-your-own-power-supply model that works with a USB phone charger, I’ll have to try that one next!)