Fun Maths
The following are some short and very cute math videos. While their beauty can likely be appreciated by everyone, they are meant for a general audience with minimal to no math background:
1) This video gives a beautiful animated describtion of how topology (and particularly Mobius strips) naturally arise when trying to solve the seemingly unrelated and simple inscribed rectangle problem: Given a closed path in the Euclidean plane, the inscribed rectangle problem asks whether it's always possible to find a rectangle with vertices located on this closed path.
1) What is a harmonic function and why are they so cool?
4) This is a nice video that explains the Gauss-Bonnet theorem to people whi are not familiar with differential geometry.