Why invest in global trouble spots?

Some of the most unpopular markets around the globe offer outsize opportunities, Mebane Faber of Cambria Investment Management said Thursday.

"A lot of these are trading at single-digit P/E ratios, all the way down to Greece, which is trading around 3, one of the lowest values we've ever seen in our database," he said.

On CNBC's "Fast Money," Faber said that beaten-down markets, such as those in Ireland, Russia and Greece, actually carried somewhat lower risk.

"One of the things about when there's proverbial blood in the streets is that you're getting a margin of safety, right? So, we've run a lot of tests, backtests, all the way to the 80s, where we show that just buying the cheapest countries outperforms the broad universe by about 4 percent a year," he said.

(Read more: Time to move into cash, strategist says)

Faber added that there was value in staying away from expensive markets, such as that of the United States.

"So, it's not that you're just buying the cheapest, you're also avoiding the most expensive," he said. "And especially when you're buying countries below 5, which is incredibly rare, and you end up with potential returns, not just for the next year, but for three and five years of 15, 20 percent a year."

Faber said that the Cambria Global Tactical ETF was long U.S. and foreign stocks, to which it would add as trends improved.

"We still have some in real estate, though we think they're overvalued," he said. "Commodities, we're pretty under-allocated even though we have an allocation to energy. And then a good chunk, about 40 percent of the portfolio, is in cash and bonds."

(Read more: 'I'd rather hold my nose' and buy Apple)

Brian Kelly of Brian Kelly Capital saw value in the strategy.

"If you have a 10-year time horizon, yes. I think it's probably a place to be," he said, adding, "It's not fast money. It's slow money."

— By CNBC's Bruno J. Navarro. Follow him on Twitter @Bruno_J_Navarro.

Trader disclosure: On Aug. 15, 2013, the following stocks and commodities mentioned or intended to be mentioned on CNBC's "Fast Money" were owned by the "Fast Money" traders: Steve Grasso is funds long FCX; Steve Grasso is funds long F; Steve Grasso is funds long MU; Steve Grasso is long BA; Steve Grasso is long BAC; Steve Grasso is long BBRY; Steve Grasso is long GDX; Steve Grasso is long GOOG; Steve Grasso is long HERO; Steve Grasso is long HPQ; Steve Grasso is long MHY; Steve Grasso is long LNG; Steve Grasso is long MJNA; Steve Grasso is long NVIV; Steve Grasso is long PFE; Steve Grasso is long QCOM; Steve Grasso is long S; Steve Grasso is long ASTM; Steve Grasso is long POT; Steve Grasso is long DECK; Brian Kelly is long US dollar; Brian Kelly is short Yen Bonds; Paul Hickey is long AAPL; Paul Hickey is long BAC; Paul Hickey is long GNRC; Paul Hickey is long INTC; Paul Hickey is long CSCO; Paul Hickey is long FB; Paul Hickey is long GOOG; Paul Hickey is long NFLX; Paul Hickey is short CAT; Paul Hickey is short IBM; Paul Hickey is short BRK/b; Karen Finerman is long AAPL; Karen Finerman is long BAC; Karen Finerman is long C; Karen Finerman is long JPM; Karen Finerman is long TGT; Karen Finerman is long GOOG; Karen Finerman is long M; Karen Finerman is long SPY; Karen Finerman is long MDY PUTS.