'NASA’s OSIRIS-REx mission and The Planetary Society invite you to submit your name for a round-trip ride to asteroid Bennu. Your name will hitch a ride to the asteroid, spend 500 days there, and return in the Sample Return Capsule to Earth in 2023.
Plus your name will be on the spacecraft, which will remain in space long after returning the sample capsule to Earth.'
Source: http://www.planetary.org/get-involved/messages/bennu/