Do you use a camera that takes AA, AAA rechargeable batteries? Do you have trouble keeping track of which batteries are fully charged and which need to be recharged?
I have developed a method that is simple and effective. I use one of the plastic cases that generally comes with batteries if you purchase them online or via mail order. You can purchase these cases separately as well.
Below is a picture of the case and you will notice that I have two arrows on the outside of the case. These are made with indelible marker. When the plus terminals of the batteries are facing in the same direction as the arrow, the batteries are charged.
When a battery is used up, the terminal goes down. Thus the in the picture below, the battery with the yellow arrow is still charged while the battery with the red arrow needs charging.
When I travel with the batteries, I use a rubber band around the case to avoid a mess if the case should be dropped. That way the batteries don’t go dancing across the floor. Good luck separating them at that point without using a meter. Rubber bands from broccoli in the supermarket produce department are ideal for this!
If this isn’t “your style”, you can click the link to see how Nick Minore has found a different way to solve this problem.