A self-portrait collection assembled without spending a single dollar will be sold off at Bloomsbury Auctions tomorrow. The house estimates that the sale — which includes pieces by John Wesley, David Hockney, and Larry Rivers — could bring in a total of $500,000.

The pieces belong to Burt Britton, a former bartender at downtown jazz club the Village Vanguard, who invited visiting literary and artistic personalities to draw a quick self-portrait. Norman Mailer was the first participant in the project, which eventually stretched for 14 years and included 2,000 works.Film stars also make appearances in the collection. Woody Allen drew a simple cartoon head (estimated at $1,200-$1,800), while Lauren Bacall drew a breezy sketch in profile ($500-$800), writing underneath, "I don’t know who this is!"

None may be more confusing than Abstract Expressionist Robert Motherwells 1976 contribution, which features just a few spare marks on paper. Is it a headless man wearing a tie or just an abstract form? It’s hard to say. For perhaps $10,000 to $15,000, though, the winning bidder will be able to ponder what it represents.