as bitcoin gets more publicity this year, people will always be there to take advantage of newcomers with the "easy money" promise.
for newcomers + for greedy people

That said, I would like to draw your attention towards a new ponzi named
weeklyponzi.com which had nearly
BTC900 circulated during its first week (it started recently), and now, its second week there, and I have seen many claiming that they earned from there. I liked the concept of the admin who actually says that its a ponzi and the ones who will invest the last day will gamble big... I know it's gonna run sooner or later, but seems an opportunity currently as whenever someone takes the txn chain ahead, the chance of you getting paid becomes inevitable... I ain't promoting them, but just saying that beware playing with these ponzis, they may turn you either into a millionaire (only in a very few cases) or may leave you broke...