The unattainable acorn
The funniest moment is when Scrat the squirrel-rat is chasing that acorn and keep failing. Everyone laughs when he appears.
Actually, come to think of it, everyone has an acorn. An acorn that you desire so much and been trying so hard to reach it, yet you are always just a few inches away from it. Aiming for that impossible target and never give up. Just keep trying and trying.
There is an acorn in everyone.