I have always been a change-saver (and maker, but that's a different story). I have kept a jar of change in my room (or now, on my living room in a fancy jar) since that time when I was two and swallowed a penny. Keeping track of change, and ensuring that I had a little "savings" from which emergencies could be covered, has helped keep me afloat time and time again.
While keeping change in a jar seems inconsequential, it allowed me to develop money sense at a very early age--and from there, a good budgeting plan that has lasted me through the struggles of college and two years as a very broke AmeriCorps volunteer. When my partner moved in with me, the money jar we started together was jointly agreed upon as the "rainy day fun fund." While we each have our own personal budget, our rainy day fund (and our household maintenance bills) have been a center point when handling finances. For me, I make sure all my spare change gets deposited into the jar at the end of the week--and at the end of the month, a portion of my paycheck gets deposited into savings.
The change jar is a simple reminder to me to be mindful of my money--and remember that it's ok to be a little silly sometimes too!