The invisible hand of the market is driving up the price of a pair of ghosts for sale on auction website Trademe.
Christchurch-based seller Melvin S is selling two vials he says contain spirits exorcised from his house and bottled.
So far, bidding had reached $410, and incited hundreds of comments, with advice ranging from how to get rid of the spirits for good, to the ethics of selling someone else's captured immortal essence.
Before the exorcism, the seller said he and his partner were plagued by noises, strange "vibes" and the mysterious flicking of switches. After contacting spiritualist churches, they were referred to an exorcist, who put the ghosts in the bottles.
Since having their troublesome housemates removed last July, the couple had experienced no further disruptions, he said.
The two spirits - an "old man" thought to be Les Graham, who lived in the house during the 1920s, and a powerful and disruptive "little girl", who apparently turned up after the couple experimented with a ouija board - were kept sleeping through holy water in the vials with them.
The seller had received, and responded to, a number of comments from sceptics, Christians, and others accusing him of charlatanism.
To one poster, who called him "absolutely sick" for selling the spirits of someone's family members, he replied "its no more sick than thinking Jesus watches us from the clouds and will return as the light lol."
To another doubter, he said: "all i have to go on is that the activity in my house has stopped now that they are bottled. :)"
Melvin S said he had tried to contact family of the old man ghost, but had so far been unsuccessful.
All proceeds from the auction will be donated to the SPCA, minus the expenses incurred by the exorcist's visit.