The Crap Ball.

My sister, Katrina, often relates her life to a ball of poop rolling down a hill. Depending on how stupid things are in her life, the crap ball rolls either faster or slower. She says that sometimes the ball will also collect random things like grass, twigs, and papers to help calm the smell--yet, the ball is still there and huge.
We were joking around about this little metaphor for Katrina's life, when I realized that my ball is made of rubber. It's not always crappy and it tends to smell kind of weird. My ball picks up materials here and there (every now and then, it will roll in dog crap and I'll hate life for a week), but it never expands. To me, this means that I take my issues in life one thing at a time. Unlike Katrina's ball, which grows and grows until she can't take it anymore, my ball bounces around everywhere and never grows. Je ne regrette rien.
However, my ball can seem big at times--even if it's the same size that it's always been. I tend to get stressed out about some things more than others. In the end, though, the ball always ends up shrinking back down to size within my mind.
So, what I want to know is what is your ball made of? And what are its characteristics? How do you perceive your ball?