Periwinkle Bockshorn operates a business called Periwinkle's Token Dispenser in
Bridgeport. The name of the shop is derived from a large copper cylinder that spans the centre of two floors of the tower, and its top is visible from the street. It has a big, funnel-like feed on the upper level of the tower. The machine will make noises and scream metal, crack wood, and jingle chains if something is thrown into the feed until a THUNK can be heard from the feed at the bottom. Then, by pushing a lever, a hatch can be opened to allow access to the result. While the output differs based on what was tossed into the funnel, it is unclear what the rules are for the "conversion". Even using items that are extremely similar results in a different outcome. Simple tests to convert lower-quality metals into higher-quality and higher-value metals failed because the resulting product is unpredictable; however, magic objects yielded the best results, so he stuck with those.

Everyone is allowed to use the dispenser, but Periwinkle requires a price of 10 gold pieces per kilogramme, and he has the authority to approve or deny what can be placed in the dispenser. Under no circumstances is it permissible to drop living beings. He is not making any guarantees about the outcome of the item conversion. People approaching him during the night pay a base fee of 100g on top.
If he is confronted with queries regarding the machine, he will deflect them by emphasising that it is his property and that they are free to utilise it or leave it alone.
GM info / spoilers / plot hooks.
The centre of the two levels of the tower is occupied by a huge rocket-like object that has become stuck there after bursting through the floor. Part of the upper level has been divided into two sections by wooden panels, one of which serves as Periwinkle's dwelling quarters.

Periwinkle's Token Dispenser by Tillerz
The door is reinforced and carries a heavy lock, all windows are barred, the hatch to the roof of the tower can only be opened from the inside.
Examples of previous conversions:
A female warrior dropped a rather cheap and rusty armour into the machine. Out came a Rust Resisting Chain Bikini +1, constantly dripping with oil.
A student put in several magical rings at once. Out came Invisible Glasses of Fabric Dissolving, that slowly dissolved any fabric you looked at, but he lost them shortly after and couldn't find them anymore, because they were invisible.
Students from the nearby
Arcane Academy visit this shop sometimes, hoping that the machine creates something useful out of their failed experiments. Periwinkle offers his services to students for 2 silver pieces per item.
This makes me want to throw random objects in the dispenser just to see what happens
Yeh, maybe I should make up some rules for that so a GM can give it a go, if a player wants to ... hm.