Great question!!! The people on this forum always think of more things than me. I think to be fair we need to measure all sales in the same currency or else our Japanese customers who sell a spinner for 1000 yen will automatically win even though that is about $8 USD.
If you sell it in another currency that is cool but also post a screenshot with conversion to USD on the date of the sale.
I'm probably going to make a new thread for this contest once we work out all the details.
Anything else I missed?