Ships going to Antarctica often offer single beds in shared cabins. When I went there, I booked the cheapest bed (maybe $6500 in 2013) in a three-person cabin.

Ships going to Antarctica often offer single beds in shared cabins. When I went there, I booked the cheapest bed (maybe $6500 in 2013) in a three-person cabin. It was early season and the ship wasn't full, so the company filled it with backpackers waiting for last-minute discounts in the hostels of Ushuaia. Because I had paid the full price, they upgrade me two classes to a much nicer two-person cabin. And then halfway through the trip, the ship delivered some staff to a museum. The other guy got their cabin, and I got the one we had shared.