Does anyone have a good solution for managing batteries when they are not in the camera? I now have eight batteries for a pair of D800s, each one numbered and dated with the date they went into service. I try to use them in numerical order just so they all get used regularly. However, they are all rattling around in some pocket in my camera bag. I found some small 9.5 ounce Glad plastic containers at the grocery store which hold four batteries, but it doesn't fit a shoulder bag very well. I'm thinking that some sort of sleeve would be ideal, but haven't found anything like that yet. Any suggestions?