“From 1. Jan. 2011, every transaction above 1,500 euros between natural persons and businesses, or between businesses, will not be considered legal if it is done in cash. Transactions will have to be done through debit or credit cards”

via HIGHLIGHTS-Greek FinMin unveils tax reform, wage policy | Reuters.

Enjoy cash while you can. I think it’s already pretty common for cash transactions in the US to seem suspicious. At some point, the government will decide that cash is primarily used to avoid taxes and cash will be phased out. As usual, the logic of state economics is pretty easy to predict.