An interesting P.O.V. (slightly tongue-in-cheek) from Lawrence Krauss.

"While the idea of sending astronauts aloft never to return is jarring upon first hearing, the rationale for one-way trips into space has both historical and practical roots. Colonists and pilgrims seldom set off for the New World with the expectation of a return trip, usually because the places they were leaving were pretty intolerable anyway. Give us a century or two and we may turn the whole planet into a place from which many people might be happy to depart."

Would you volunteer for a space mission, even if it meant you would never return?