We ran this in Freiburg, Germany in January 2023 with a total of 10 people.
It was very fun!
Many people had never explicitly thought about such rates of exchange and they found the implications interesting
Some people were able to identify inconsistencies at the end while going over their list of bookings
Worthy of improvement / Unclear things:
In the trade I am giving up what I have on my card. Can I give up more than one item? Do I already own that item beforehand? If I am giving up several is it because I own all of them or do I need to get them somehow (e.g. by paying money)? For example if my index card says “An apple” and the other person’s index card says “1 million USD”, would I trade my single apple for a fraction of the million USD or would I trade many tons of apples for the entire 1 million USD. Do I already own those tons of apples?
We solved this by specifying that you own your item once and always trading for a fraction of what the other person owns.
Including monetary values like “1 million USD” makes it less fun because those exchange rates are more common anyway
Some things are really hard to multiply or subdivide such as “the ability to breathe underwater”.
We solved this by specifying that the fraction was having this ability for a certain amount of time instead of the rest of your life
Since my booking card always compares everything to my own “index card” I don’t ever get any obvious inconsistencies. e.g. I only have trades involving the “mediocre laptop” with the plane ticket, with the bicycle, with everything else. But never an exchange between the plane ticket and the bicycle.
The inconsistencies only become clear once you start comparing the things on your booking card among themselves, which is made more complicated by the fact that you had to use fractions or multiples in the other trades. It would be great if these inconsistencies become directly obvious as part of the game rules e.g. by trading index cards at some point.