When the Beverly Hillbillies struck oil on their land, they instantly knew they were millionaires. Finding oil was, and still is, the equivalent of finding an Aztec tomb filled with gold and jewels or winning the lottery a hundred times over.

But the world is changing, and there's a new type of fuel to run it: Data. "Just as the politics of oil shaped the 20th century industrial economy, so the politics of data will shape the 21st century digital economy," writes Andrew Keen through CNN.

We're in a digital economy where data is more valuable than ever, and it is the key to the smooth functionality of everything from the government to small ad agencies. Without it, progress would halt.

The European Commission Vice President for Justice Viviane Reding vs. Facebook Chief Operating Officer Sheryl Sandberg
At this week's Digital Life Design (DLD), an annual technology conference in Munich, Reding and Sandberg discussed access to data and all the privacy and control issues that come with it.

Reding argued, "the great threat to individual liberty in the digital age comes from companies that use our data to enrich themselves -- buying and selling our most intimate details for their own corporate benefit." She calls for tighter legislation on what companies can do with data and how they can access it.

"To this end, Reding is introducing legislation which will give consumers the right to be forgotten on online social networks like Facebook and Twitter," reports Keen.

Sandberg takes a different approach. She calls the digital revolution "a really big deal." She claims we increasingly identify ourselves with our online presence. "Above all," continues Keen, "it turns all of us from being passive receivers of other people's information into active broadcasters of our own lives."

Who do you think is right?

Business section: Investing ideas
So, if data really is the oil of the digital age, we were wondering how to give a portfolio exposure to this rapidly growing industry.

To explore the topic, we've included a list of the 10 biggest data storage companies trading on U.S. markets. Use this list as a starting point for your own analysis.

List sorted by market cap. (Click here to access free, interactive tools to analyze these ideas.)

1. EMC (NYSE: EMC): Develops, delivers, and supports the information and virtual infrastructure technologies and solutions.

2. NetApp: Engages in the design, manufacturing, marketing, and technical support of networked storage solutions.

3. Western Digital (NYSE: WDC): Engages in the design, development, manufacture, and sale of hard drives worldwide.

4. Seagate Technology (NYSE: STX): Designs, manufactures, markets, and sells hard disk drives for the enterprise, client compute, and client non-compute market applications in the United States and internationally.

5. Brocade Communications Systems (Nasdaq: BRCD): Brocade Communications Systems, supplies networking equipment comprising end-to-end Internet protocol based Ethernet and storage area networking solutions.

6. Fusion-io: Focuses on the development, marketing, and sale of storage memory platforms for data decentralization.

7. Emulex: Provides network convergence solutions that connect servers, storage, and networks within the data center.

8. Quantum: Operates as a storage company that provides backup, recovery, and archive solutions to small businesses to multinational enterprises in the United States and internationally.

9. Ocz Technology Group (NYSE: OCZ): Designs, develops, manufactures, and distributes computer components for computing devices and systems worldwide.

10. Xyratex: Provides modular enterprise-class data storage solutions and storage process technology.

Interactive Chart: Press Play to compare changes in analyst ratings over the last two years for the stocks mentioned above. Analyst ratings sourced from Zacks Investment Research.

List compiled by Eben Esterhuizen, CFA. Kapitall's Eben Esterhuizen and Rebecca Lipman do not own any of the shares mentioned above.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.