what is up with the 100 coin Withdrawal fee at C-Cex.com for Prozcoin? Seems a bit excessive.
Mastercoin works by placing a layer on top of the Bitcoin Blockchain, in order to do this, every transaction requires a small amount of bitcoin to travel with (currently 0.003 BTC) I think that amount is decreasing drastically in the future (more like 0.0005) I assume withdrawal fees are used to offset this cost to the exchange.