In 1905, Picasso painted a self-prortait of himself sitting at the bar dressed as a harlequin in "At the Lapin Agile." When he ran short of cash he traded the painting to Frédé for a hot lunch. Frédé didn't think much of it so in 1912 he sold it for about $20 USD equiv. It last changed hands for $41 million USD.
The Au Lapin Agile cabaret, still there and still open for business
Paris' most important art show was the by-invitation-only "Salon," which habitually spurned the modern artists, so they held an exhibition all their own, which they called the "Salon des Indépendants."
To prove his point, Frédé tied a paint brush to the tail of his pet donkey, Lolo, stood it in front of an easel and canvas, then teased it with its favorite treats to encourage it to swish its tail.
An after-the-fact recreation of the event
They signed the work "J.R. Boronal" and entered it in the 1910 Salon des Indépendants, claiming it was the work of a Genoese painter and an adherent to the new "Extremist" style.
The painting received generally positive reviews and sold to a collector for 20 Golden Louies, about $1800 USD adjusted for inflation.
Frédé and his friend, Lolo.
In any case, this is a vintage photo of Au Lapin Agile:
And this is cabaret impresario Frédéric Gérard and Lolo: