They're gold diggers of the new millennium, sifting for fortune amid soaring prices for the yellow metal.

But today's gutsy investors are panning for gold in very different ways.

Just as California's Gold Rush in the 19th century drew miners to the West with different strategies on how to profit, some of today's most notable investors are pursuing distinct tactics to wager on a rise in gold. Some are scooping up exchange-traded funds and mining companies. Others are betting on futures and derivatives markets. Still others are storing vast amounts of gold in secret warehouses in the U.S. or in foreign countries.

Some of the investors making the biggest bets on bullion are well worth watching. John Paulson and David Einhorn were early predictors of the subprime-mortgage and financial meltdown of 2007 and 2008. Thomas Kaplan and John Burbank were wagering on mining shares several years ago, when their rivals snickered.

Gold prices have been climbing amid worries about leading currencies and future inflation. Other factors include a growing number of ETFs and other investment vehicles that offer plays on the commodity. It's also getting harder to tap new ore veins, limiting supply.