I like to re-use things whenever I can, and these old peanut butter containers have worked really well as change jars! They're plastic, so I don't have to worry about them breaking if they get dropped, and they don't get unmanageably heavy when they're filled with coins, either.
These particular change jars came in very handy a few weeks ago when we began to run low on cash. I took them in and converted all of our coins into "paper money" (as our kids call it), and we had $153.83 worth of coins! I know people who throw away pennies instead of going to the trouble of storing them. The coin counting machine told us that we had 1563 pennies -- which is well worth the trouble of storing them, if you ask me!