Entropia Universe is a massively multiplayer online virtual universe esigned by Swedish software company MindArk, based in Gothenburg. In contrast to other similar MMORPGs, MindArk's software is distributed free of charge with no subscription fees. The developers instead have decided to use a variant of the micropayment economic model, which consists of buying in-game currency (PED - Project Entropia Dollars) with real money that can be redeemed back into real world funds at a fixed exchange rate with the US dollar, where 10 PED = $1 USD. This means that virtual items acquired within Entropia Universe have a real cash value, and a participant may, at any time, initiate a withdrawal of their accumulated PEDs back into real world currencies according to the fixed exchange rate, minus transaction fees. As a result, revenue of the business is largely generated from activities within the virtual universe. The revenue model has historically proven to be sustainable and is currently profitable.