Forex? It's Scam or Opportunity?

I have been intrigued with Forex (short for Foreign Exchange, or foreign currency trading) for sometime. I've heard many times from many different sources that a good forex trader can average one-half percent on his invested capital per day. That doesn't sound like much until you realize it works out to about 250% per year. Whenever I've run into anyone who trades forex, I've asked them about that figure, and each one has confirmed it. But none of them are living like they have the kind of money that return would generate. (Starting with $1,000, that return achieved consistently would yield over half a million dollars in 5 years).