The green-energy get-rich-quick schemes are showing up in blog posts, e-mail, infomercials, Internet message boards, text messages, and Twitter. As with most investment scams, all promise unrealistic returns, such a 200 percent stock gain by a solar panel company, a one-in-a-million deal to get a "51 times" return on current stock value from a China wind-power enterprise, and a 500 percent one week stock gain by a hydrogen-based energy outfit.

Of course, the regulators are on the lookout for the scammers. In one recently filed case, the SEC charged that promoters of eco-friendly investment opportunities lured 300 investors into a $30 million Ponzi scheme, encouraging the participants to finance "green" initiatives of Mantria Corporation, including a purported "carbon negative" housing community in rural Tennessee and a "bio-char" charcoal substitute made from organic waste. Investors were promised returns ranging from 17 percent to "hundreds of percent" annually. But, according to the SEC's complaint, Mantria did not generate any income from which such extraordinary returns could be paid.

As cautioned by the SEC, the oil spill in the Gulf of Mexico brought additional scam opportunities for cons promising financial gains from investments in companies that claim to be involved in the cleanup operations. In May and June 2010, the SEC suspended the trading in shares of ACT Clean Technologies Inc. of Huntington Beach, CA, and Green Energy Resources, Inc. of New York, NY, because, among other issues, questions arose about the accuracy and adequacy of the publicly disseminated information by the companies.