Artists Tracey Emin, Anish Kapoor and Yoko Ono have all donated pieces to this year's Secret Postcard sale at London's Royal College of Art.
Over 1,000 artists have donated work to the event, now in its 16th year.
This year, 2,700 works by professional artists and students are being sold to raise money for the RCA's Fine Art Student Award Fund.
Photographer David Bailey, former Stone Roses guitarist John Squire and animator Nick Park are among contributors, along with fashion designers Paul Smith and Manolo Blahnik.
The artists' identities are kept secret until works are bought. Each postcard is signed by the artist on the back.
Many leading American artists have also contributed this year including Bill Viola, Lawrence Weiner, John Baldessari and Alex Katz.
Potential buyers can view all the postcards at the Royal College of Art ahead of the 21 November sale.
The exhibition was the brainchild of an RCA student in 1994.
Each postcard costs £40 but buyers could potentially end up with an artwork worth much more than that.
This year, German artist Gerhard Richter has donated a work for the first time.
To date, sales of postcards have topped £1m for the fund, helping hundreds of emerging artists.
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