"I've seen folks put a half-million dollars into them," says Joseph Borg of the Alabama Securities Commission.
Telltale signs of a scam: promises of guaranteed outsize returns and pressure to invest quickly lest this incredible opportunity pass you by.
In nearly all states, projects and agents need to be registered or licensed when oil is concerned, so check with your state regulators.
NEXT: Buy low - the brave way
Last updated August 16 2008: 4:37 PM ET