About 2,700 professional artists and students have contributed to this year's Secret Postcard event at the Royal College of Art (RCA), in London.

Each postcard features an original design, and cost £40 each. The artist's name is revealed once the postcard has been purchased.

Artists contributing to this year's sale include Tracey Emin, Yoko Ono, Grayson Perry and Wallace and Gromit creator Nick Park.

The postcards will be exhibited for a week from Friday, then will be sold on 22 November on a first come, first-served basis.