I've used a small camera bag ($5 Walmart model), a cigarette purse and several coin purses. Camera bag is best so far. Not for show, just keeps shells clean and protected in pockets and saddle bags.
I just got this shot shell pouch from the Ruger store...it's made by Triple K, and good heavy leather. It is open inside (no shell loops), and 2 speed strips loaded with 5 rounds each fit nicely inside it. Plus it has the Ruger logo on it.