A group in New York has started a new craze known as TipBombing.
The stunt involves organising crowds of people on Facebook to gather around an unsuspecting street musician at a prearranged time and donating money en masse.
The first recipient was Robert Leslie, a musician from the UK.
The second TipBombing happened a week later, to Guitaro 5000.
Organiser Vito Catalani told Brokelyn that the project was a way to appreciate "these individuals who contribute so much to the culture and vibe of New York City".
He added that it wasn't easy "to choose [who to tip] with so many great artists populating the streets", but they target the performer they "believe deserves the most recognition because of their talent, originality, uniqueness, and positive vibe they push out every day".