I sort out my SPP .45 cases, and store them away in big Folgers containers. I had about 2500 saved for emergency times, but ended up trading away 1500 of them for 1500 LPP .45 cases. I meet a reloader at a IDPA match that has switched to SPP cases to reduce the # of different primers he keeps on hand. I figured I would hang on to some for a just in case situation. Besides I usually bring home a couple hundred .45, and 9mm cases along with my .40's I shoot at matches.
As a reloader I have learned to not leave brass on the ground. I picked up brass of all calibers. It makes good trading fodder. I just made a trade with a good friend in January: I had about 4,000 9mm cases cleaned that I traded him for 3,500 .223/.556, and 1,200 .40s&w cases. He's retired, and goes out to the range at his gun club to collect brass after pistol, and carbine training classes.