How much does a cup of coffee cost in Belfast's Titanic Quarter?
If you thought £1, £2 or even £3, you would be wrong.
Because in one cafe, a cup of coffee costs exactly whatever you think it's worth.
The Dock Cafe opened last week and instead of a till, it has an honesty box.
The cafe, run by the Docks Church, asks customers to enjoy their tea, coffee and whatever buns and biscuits they want and then leave a contribution on their way out.
If that's unheard of, the interesting thing is that so far, the cafe management believes it has made more money that if it were charging £1.95 for a cup of coffee.
The cafe is near where the SS Nomadic sits in the Titanic Quarter and has been granted a "meanwhile lease" for commercial premises.
That means it can operate without paying commercial rent and just covering the running of the cafe.
Rev Chris Bennett, the chaplain for the Titanic Quarter, said the scheme has been a huge success so far.
"We are here on a meanwhile contract, which means that we are just a little pop-up cafe until a commercial tenant comes along at some future stage," he told Evening Extra.
"Under the meanwhile contract we are not a commercial enterprise, we are actually a charity, we are a church group.
"Our long term hope is about saving up for a boat. We want to be based on a boat and have that boat as our shared chaplaincy space.
"In a way this cafe is the dry dock, it is a temporary means of hopefully having our boat here one day."
And the takings from the honesty box have been even better than expected.
"We have had the lovely experience so far that every time we have emptied the honesty box at the end of the day there has been more than we expected," he said.
"At this point I think we might even have a little bit more in the honesty box than if we were charging £1.95 for a coffee.
"Belfast people are good people. I am not surprised but I am pleased."