If you have kids in your house, you are probably all too familiar with the dilemma of markers with no caps and marker caps with no markers. I used to put plastic wrap on the markers, tied with a rubber band, to keep them from drying out. But, that was no real solution. One day, I got a little baggie and put the caps in it. Now, any time I find a marker with no cap, I go looking in my baggie and find a marker cap to put on the end. That way the marker doesn't dry out and I save some money!
I wish I had thought of that when my kids were little.
I save the marker caps too but use them for other things like the handle for homemade stamps and for making the handle on a spinning top made from an old cd and a marble for the spinner tip.