There's nothing wrong with pursuing new investment ideas that include both out-of-the-box thinking and huge gains. For some investors, that's been the lure of the cryptocurrency bitcoin.

But aside from its massive volatility, many investors don't like the idea of investing in something that doesn't, well, have assets that actually grow. For investors who are looking for investments with lots of potential, but that are more traditional than bitcoin, consider Stitch Fix (NASDAQ:SFIX), Foundation Medicine (NASDAQ:FMI), and (NASDAQ:AMZN).

Person holding coin with stock chart in the background.

Image source: Getty Images.

A young company with big upside potential 

Jeremy Bowman (Stitch Fix): Bitcoin investors aren't afraid of risk and are seeking huge returns. But instead of betting on a cryptocurrency with virtually nothing underpinning its value, you may want to take a look at this recent IPO with big things ahead: Stitch Fix.

The e-commerce clothing company debuted in November, and the stock has already gained more than a third following a solid earnings report in December. Stitch Fix is unique kind of company on the market. It's a subscription styling service that sends clothes, shoes, and accessories to customers after they fill out detailed profile with information on style, taste, and fit. Shoppers keep what they want and return the rest. 

Just as Netflix disrupted video entertainment through e-commerce and Amazon disrupted so many other categories, Stitch Fix has the opportunity to do the same thing with clothes. The company claims that its data science, or customer data and proprietary algorithms, give it an advantage in selecting and designing apparel for its customers, and the results speak for themselves. Founded in 2011, the company is already profitable and has reached $1 billion in annual sales. 

Stitch Fix has just expanded into men's and plus-size, which should help drive sales growth, but its biggest opportunity may be in Exclusive Brands, or private-label items that the company designs itself, as its trove of data and customer relationships should help it design better, more stylish, and more comfortable clothes.

Stitch Fix is certainly a risky stock as it's a start-up competing in an unproven space, but at a market cap of just $2 billion, there's huge potential for growth if the company can execute effectively.

Cashing in on genetic medicine

Todd Campbell (Foundation Medicine): Buying companies like Foundation Medicine that are backed by a growing business could be a better bet than worrying what the next big cryptocurrency may be.

Foundation Medicine is at the forefront of innovation in how we treat cancer. Increasingly, cancer drugs are being developed that target specific genetic mutations that cause cancer growth or support resistance to existing drugs, so discovering which patients are best treated by these new drugs is becoming incredibly important.

Foundation Medicine's solution doesn't just screen a cancer patient's genetic code for mutations, either. It also provides doctors with a list of approved drugs and drugs in clinical trials that may work best. This revolutionary approach to personalized medicine is unprecedented, and in my view, it's the future of cancer treatment.

The company's already experiencing rapid growth. Recently, management unveiled preliminary 2017 revenue of $48.9 million in Q4 and $152.9 million for the full year. Those figures represent year-over-year growth of 70% and 31%, respectively. Sales momentum is likely to accelerate in 2018 following the recent FDA approval of FoundationOne CDx, the first FDA-approved broad genomic profiling test.

Management thinks about one million advanced cancer patients per year in the U.S. could benefit from genetic testing, yet only 15% are currently getting comprehensive screening. I expect genetic screening will become far more common when FoundationOne CDx gets a specific Medicare reimbursement code, which could happen in the next year. Additionally, the addressable market for screening should increase as testing moves into earlier stage treatment and an aging population increases cancer prevalence.

I'm also a fan of Foundation Medicine because of its partnership with Roche Holdings (OTC:RHHBY), one of the world's biggest cancer drug makers. Roche Holdings owns more than 50% of the company, and a stand-still agreement preventing Roche from buying or selling shares ends in April 2018. Given the opportunity associated with genetic testing and its deep-pocketed partner, I think owning Foundation Medicine is a better bet than buying bitcoin.

If huge gains are what you're looking for

Chris Neiger (Amazon): If you're chasing bitcoin because of its huge gains and future potential, then let me introduce you to a stock that has both of those -- plus far more stability. Amazon is, of course, an e-commerce giant. The company earned 90% of its top line from its e-commerce sales in the latest quarter alone, but the company is far, far more these days.

Amazon CEO Jeff Bezos has morphed the company into a massive cloud-computing player that now holds the majority -- 40% -- of the public cloud market. Amazon's Web Services (AWS) brought in $1.2 billion in operating income in the third quarter, compared to just $112 million in operating income from its-e-commerce business. Cloud computing will be worth an estimated $411 billion by 2020, and with Amazon's current lead, and its current partnerships, it's poised to gain from this market even more in the coming years.

Aside from from its e-commerce and cloud dominance, the company has expanded into artificial intelligence services for developers, is leading the connected home space with its Echo devices and Alexa virtual assistant, and recently got into the grocery store business by snatching up Whole Foods.

All of this gives Amazon a heaping dose of assets that bitcoin will never match, along with share price gains that even cryptocurrency followers will love: Over the past three years, the company's shares have skyrocketed 335%. Sure, Amazon's shares are trading at a hefty premium of 162 times its forward earnings, but if you're seriously considering bitcoin, then Amazon's premium looks like a bargain.

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.