You've doubtless heard of the Oracle of Omaha and every investor's patron saint, Warren Buffett.

However, there are billionaire investors who you've probably never heard of, largely due to the fact that they don't get the same fawning publicity as their peers. To enlighten you, and perhaps stimulate a slight feeling of envy, here's a quick look at five fabulously -- but obscurely -- wealthy investors, past and present:

Li Ka-shing

Li is Asia's richest businessman. As head of the conglomerates Hutchinson Whampoa and Cheung Kong Holdings, his empire spans the globe and accounts for nearly 15% of Hong Kong's stock market value capitalization of $2.3 trillion.

Li's business controls 12% of all container port capacity in the world. Li Ka-shing also holds wide investments in telecommunications in the Pacific Rim and Europe. Yet through it all, this 82-year-old billionaire, currently the wealthiest person of East Asian descent in the world, continues to wear simple black dress shoes and an inexpensive Seiko watch.

Li's strategy is simple but effective: He invests in high-quality infrastructure assets in stable, non-cyclical industries. These assets also tend to be tightly regulated. Not sexy, but his patient and methodical accumulation of container ports has paid off. His wealth is estimated at $12.4 billion.

Lakshmi Mittal

Born in India in 1950, Mittal, now living in London, is the CEO of Mittal Steel Co. Starting with the family-owned steel business in India, he built the modest company into a powerhouse steel producer with facilities in more than a dozen countries.

He was in the vanguard of the 'mini-mill' revolution in steel production, which helped propel Mittal Steel into the largest steelmaker in the world, with annual shipments of more than 42 million tons and annual profits in excess of $22 billion.
Mittal invested in distressed steel producing facilities with bloated production methods. He would shed unnecessary and overly expensive production capacity, to create smaller, nimbler steel plants that engaged in 'lean manufacturing' and just-in-time inventory management. The result: lower overhead, more efficient operations and higher profits. Mittal's wealth is estimated at $25 billion.

Kerry Packer

Aussie media mogul Packer passed away in 2005. In his heyday, he was Australia's richest man, as the owner of Publishing and Broadcasting Ltd., which owns pay-TV channels, and Australian Consolidated press, which owns 60% of the Australian magazine market.

Packer suffered a hard-scrabble youth, which included a bout with polio and treatment in an iron lung. His father Sir Frank Packer founded the media empire during the Great Depression with Women’s Weekly magazine. Kerry Packer took those humble beginnings and built a media empire that now includes casinos and tourism.

Perhaps because of his origins, Packer had an innate sense of what average consumers of media wanted, and he gave it to them by turning moribund media properties into more colorful purveyors of news mixed with entertainment. At the time of his death, he was estimated to be worth $2.4 billion. His son James now runs the business.

Wilbur L. Ross, Jr.

Today, Ross is known for making his fortune as a 'vulture investor' who restructures bankrupt companies in the steel, coal, textiles, and telecommunications industries. He is considered the maestro of leveraged buy-outs in unglamorous 'rust belt' sectors. But he didn't earn this title until 2000, when he left his long-time career as a bankruptcy advisor to start his own investment fund, specializing in failed but inherently promising companies. Considering Ross was born in 1937, you could say he's a late-blooming billionaire. [In our recent article about the 13 Best Job Sites for Baby Boomers, we highlight websites that help boomers take the next step in their careers, just like Ross did.]

One of Ross' first big deals was to buy and 'flip' the distressed International Steel Group to Mittal Steel for $4.5 billion in 2005. He performed similar feats, by combining Burlington Industries and Cone Mills in 2004, to form International Textile Group. His net worth is estimated at $1.7 billion.

Lev Leviev

Leviev is an Israeli-based businessman and diamond mine investor.

In 1971, when Leviev was 15, his family immigrated from Uzbekistan to Israel. It was there that the future-billionaire got his start as an apprentice in a diamond polishing facility, learning the basics of diamond cutting. After serving a stint in the Israel Defense Forces, he founded his own diamond polishing plant.

When the Soviet Union fell in the early 1990s, Leviev shrewdly rushed into the former communist bloc and expanded his business interests throughout Eastern Europe, getting in on the ground floor of capitalism's nascent expansion there. Today, his diamond business is considered a major competitor to industry heavy-hitters like De Beers and the Harry Winston Diamond Corporation (NYSE: HWD). In addition to diamonds, he holds vast interests in real estate and chemicals. In Russia, he is heavily invested in residential real estate and shopping malls. One of the keys to Leviev's success has been his knack for getting in on the ground floor whenever he senses a boom is imminent.

His net worth is valued at roughly $1.5 billion.