Stocks have done great, so maybe they're too pricey for a new investment. Bonds look awfully risky. The easy money has been made in investment properties. And gold? Well, that's for a certain sort with an apocalyptic outlook.
Here's a thought: wine and whisky. Values of some labels have skyrocketed in recent years, and a growing supply of well-heeled collectors from Asia and elsewhere could drive prices even higher. Expensive wines and whiskys could truly diversify a portfolio.
Wine investor and collector Kenneth Waltzer, founder and president of California wealth-management firm Kenfield Capital Strategies, says he started drinking quality wines as a young man. He fondly recalls sipping a "fabulous" Bordeaux from the 1920s at the time.
(Read more: Score big cash for fine wine)
Waltzer started serious collecting in the early 1980s and sold a chunk of his holdings in the late '90s for enough cash to start a business. The value of his collection had almost tripled in 10 years, he said. One case of 1986 Bordeaux, bought for $700 in 1988, soared to $4,500 in the decade Waltzer owned it.
Some whiskys also have produced big returns in recent years, making that spirit a growing niche investment, although still tiny compared to wine.
Financial experts urge investors to be careful, however. This world is filled with risks not encountered in other investment arenas. These include the chance some expert will slam your vintage, causing demand to evaporate, or that your fine wine will turn out to be counterfeit—or turn to vinegar.
(Read more: Using alternative strategies for "average" investors)
"It's all about provenance—where it has been and who has stored it, and can you prove it," Waltzer said.
So he and other experts caution against leaping in with both feet. In other words, don't dump your bonds for bottles.
"There's an old joke," said wine investor Stephen F. Lovell, who is a certified financial advisor and branch manager for LPL Financial. "How do you make a small fortune in wine? You start with a large fortune."
It's apparently difficult to find professional help when it comes to wine and/or whisky investing.
(Read more: Gallons of whisky dumped down drain)
Wine advisors are geared to serve connoisseurs who want bottles that get more delicious—but not necessarily more valuable—with time. There are wine appraisers, of course—most of them working for art-appraisal houses—but it would be too expensive to hire one to advise on every small purchase.
In addition, the wine-and-spirits investment market just isn't big enough to support financial advisors specializing in it. And the ordinary financial advisor is lost in this world, although it would be smart to ask yours how much you can afford to bet on something this iffy.
Still, there are plenty of stories of people making money by collecting wines. And although whisky collecting is new and a much smaller field—it's always best to get in on the ground floor if you can stomach a wild ride, right?
So how would an investor get started?
"A lot of people probably start like I did, where it's something that's part of your life," Lovell said. "That doesn't make you a good investor, but that can get you thinking about it."
Then, said Waltzer, start building your knowledge.