A Canadian man is hoping to be the first person to sell his house for virtual currency Bitcoins.
Entrepreneur Taylor More listed his two-bedroom Alberta bungalow, asking 405,000 Canadian dollars (£261,000; $395,000) - or the equivalent in Bitcoins.
He says the first reaction of his family was that of a shock.
Bitcoins are now a widely used alternative payments system and one Bitcoin is currently worth about £37.
"Bitcoins are really hard to get your hands on if you want to get them in large quantities," Mr More told the BBC.
"I have a couple projects that I want to get started, and they will take a lot of Bitcoins."
He did not get into detail on his new venture, only saying that it should "get Bitcoins more mainstream".
Privacy for users
Unlike other currencies, Bitcoins are not issued by a central bank or other centralised authority.
They first appeared in 2009 and are closely linked to the global network of computers which supports the currency and its users.
People generate or "mine" Bitcoins by participating in that network - for instance, by solving a complicated mathematical problem using their computer.
A growing number of web stores and online firms accept Bitcoins as payment.
Bitcoins can be exchanged for "real" money, and they can be used to make transactions that are difficult to trace, offering privacy to their users.
The currency has been adopted by Wikileaks and other sites to receive donations.
"It's an instant form of payment, and there's very low cost transfer fees," said Mr More.
"When you send money internationally it takes a week or more to do and costs hundreds of dollars, so I see this as something we've needed, an online virtual currency to make payments fast and easy."
The use of Bitcoins has been slowly spilling from the online into the physical world - for example, it is now possible to use the currency to buy pizza.