For those who have everything, how about a Soviet-era space capsule dating back to the 1970s, when it carried three cosmonauts into space?
German firm Lempertz unveiled plans Wednesday for what it says is the first such auction in Europe, with the capsule expected to fetch up to 1.4 million euros ($1.9 million) on May 7.
"It was developed during the Soviet-US space race, part of the Cold War," the auction house said.
A British company first bought the capsule, which was also used for a short unmanned mission in 1978 and then for training, it said.
It then decided to sell, handing it to Lempertz to manage.
The capsule has been extensively restored, removing all trace of the searing burn marks it picked up on re-entry to the earth's atmosphere.
Now it is a newly painted pristine white, measuring some 2.2 metres (seven feet) high and 2.8 metres in diameter, weighing in at nearly two tons.
A circular door opens into the cramped compartment where the cosmonauts sat during their voyage around the earth.
Lempertz said it was organising the sale to mark the opening of its office in Brussels, aiming to attract attention with the highly unusual lot, known as Vozvrashchayemi Apparat (VA), or "re-entry capsule" in Russian.
Besides the capsule, also going under the hammer are its command panels plus two more recent space suits, estimated to fetch up to 60,000 euros each.
Explore further: American, two Russians back on Earth after half-year in space (Update)