Help catch whoever is responsible for the missing 600K BTC from Mtgox.
More than 650,000 BTC of customer money is missing. Mark Karpeles is refusing to cooperate with investigators to track down the missing bitcoins.
It was announced that around 850,000 bitcoins belonging to customers and the company were missing and likely stolen, an amount valued at more than $450 million at the time. Although 200,000 bitcoins have since been "found", the reason(s) for the disappearance—theft, fraud, mismanagement, or a combination of these—are unclear as of March 2014. There has been some speculation of hackers being responsible for the missing Bitcoin, but no case has been proven.
More details at Suspension of trading 2013 (Wikipedia)