Musician Frank Aumann expertly played an emergency siren sound on his accordion while riding hands-free on his bicycle.

Matt Lyons hilariously poked fun at the obsessive knowledge of birds that people develop after installing a bird feeder in their yard.

"There I Ruined It" cleverly remixed the sound of four thrashing washing machines to play Rage Against the Machine's "Killing in the Name".

Urban explorer Paul Stout explained the concept of "desire paths", the shortest path taken, often evidenced by worn patches in the ground.