Apparently major banks and broker dealers are already preparing themselves for the Greek withdrawal from Eurozone and a return to Greek Drachma currency scenario as according to multiple reports ICAP and others are testing their electronic trading platforms.
ICAP is the latest firm to disclose such preparations, joining the growing ranks of banks, governments and other key players in the global financial system whose officials are worried enough about the stability of the common currency to be making contingency plans for a possible break-up.
Regardless of the financial turmoil such move will surely create this posses an opportunity as well as a headache for retail Forex brokers. Such move would require them to add several additional currency pairs to their platform (remember that Metatrader has a limit on pairs, and some brokers may already be maxed out), plug Liquidity which is a big headache as nobody really provides a proven feed for a currency that still doesn't exist and then test it all. On the other hand those who can make market on Drachma pairs will be in a great position to benefit from all the liquidity flowing their way and adding another currency pair may attract new traders and create more volume for brokers.
Hopefully however for the sake of stability of financial markets (and my pension) this is just a hypothetical scenario.