Special Report

America's Most Unusual Public Companies

1. Clean Energy Fuels Corp.
> Business: Gas station
> Market cap: $812 million

Clean Energy Fuels Corp. (NASDAQ: CLNE) is not your run-of-the-mill gas station company. Rather than diesel or gasoline, the company’s gas stations only provide natural gas transportation fuels. The company aims to be the destination for a nationwide fleet of natural gas and compressed natural gas-run trucks. Clean Energy has close ties to billionaire and energy guru T. Boone Pickens, who serves on its board of directors and owns 24% of the company. It claims to deliver more natural gas transportation fuel than any other company in the United States. Clean Energy also claims that it fuels more than 35,000 vehicles each day at approximately 500 fueling stations in the U.S. and Canada. The company’s top line has grown, reaching $352 million in 2013. Analysts expect sales will grow to almost $500 million by the end of 2015.

2. GW Pharmaceuticals
> Business: Biotech
> Market cap: $1.1 billion

With marijuana now legalized in two states and decriminalized or medically available in many more, this is a hot area. While U.K.-based GW Pharmaceuticals PLC (NASDAQ: GWPH) does not provide what is commonly referred to as medical marijuana, its products include cannabis ingredients. GW can therefore be seen as a medical marijuana play. More accurately, though, the U.S.-listed company is a biotech outfit developing cannabinoid medicines. Its Sativex drug, which targets multiple sclerosis spasticity — stiffness and involuntary muscle spasms — has already been launched in 11 countries and approved in 13 more, although not yet in the United States. The company is also looking to target cancer pain with Sativex, and its drug pipeline includes Epidiolex, a potential treatment for childhood epilepsy.

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3. World Wrestling Entertainment
> Business: Pro wrestling
> Market cap: $1.3 billion

Vince McMahon has built World Wrestling Entertainment Inc. (NYSE: WWE) into global wrestling empire over the years. The company recently launched the WWE Network. The network, which had 667,000 as of April, seems well on its way to reaching its stated goal of 1 million subscribers by the end of this year. Despite some concerns about a shift to online viewing and away from live events and pay-per-view, WWE has managed to steadily grow its revenues. Sales were $508 million in 2013, versus $478 million in 2010. The WWE Network is expected to grow revenues to $581 million in 2014 and to nearly $800 million in 2015. In addition to the network, WWE also hosts Wrestlemania — the professional wrestling’s equivalent of the Super Bowl. Its investors currently receive a 2.8% dividend yield.

4. RPX
> Business: Patent risk management solutions
> Market cap: $862 million

RPX Corp. (NASDAQ: RPXC) provides patent risk management solutions. This means the company acquires patents for the express purpose of protecting its customers, who pay an annual subscription fee, from patent litigation. RPX was founded in 2008 and has been publicly traded since 2011. In addition to defensive buying, the company advises clients on patent acquisition, provides market research and even litigation insurance. Sales have risen consistently in recent years, up from $33 million in 2009 to $238 million in 2013. The handful of analysts covering RPX see sales growing to more than $292 million by the end of 2015.

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5. Collectors Universe
> Business: Collectible evaluation
> Market cap: $199 million

Collectors Universe Inc. (NASDAQ: CLCT) is unique to the field of sports collectibles, serving as a grader and authentication service for collectors of sports cards, autographs, memorabilia and coins. It claims to have certified more than 50 million collectibles to date. Revenue in its latest fiscal year totaled $49 million, and net income was $5.73 million. Collectors Universe has competition in sports card grading and in other aspects of its business, but it is unique in that it is publicly traded. In the company’s most recent nine months, its service revenue increased by 26% from the same period last year to nearly $44 million, a company record. Currently, the stock has a dividend yield north of 5%. The company is very small, with a market capitalization of less than $200 million.