So you're interested in bitcoin, Ethereum, and other new-age cryptocurrencies. But you have found it difficult to actually use your digital assets for anything other than trading them for other cryptocurrency names.

In that case, (NASDAQ:OSTK) wants you as a customer.

The online retailer has been bullish on Bitcoin and other blockchain solutions for years now, and is only moving deeper into alternative payments. This week, Overstock partnered up with e-currency exchange service ShapeShift to allow customers making payments through a ton of cryptocurrencies not named Bitcoin.

Ethereum logo, grayscale on a blank field.

Image source: The Ethereum Project.

What's new?

ShapeShift provides e-currency exchange tools that let you trade one blockchain-based currency for the equivalent amount of another one. In the Overstock agreement, the retailer will use ShapeShift to translate other types of e-payments into Bitcoin, which the company already knows how to accept as payment for its e-commerce goods. Compatible non-bitcoin currencies include Ethereum, Litecoin, Dogecoin, Dash, Ripple, and literally dozens of others.

So Overstock's checkout process will ask you for a payment source, including a long list of ShapeShift-ready cryptocurrencies. When you select something like Litecoin or Ethereum, ShapeShift will accept your transaction and translate it into a chunk of bitcoin, which is then sent directly to Overstock. No further action needed from the shopper. Any refunds of these transactions will be given in Bitcoin, though Overstock points out that ShapeShift can help you move back to the original currency as well. It's just not automatic.

What's the big deal?

The ShapeShift contract does nothing for people who already use bitcoin for shopping at, but it does expand the addressable market considerably. The addition of Ethereum alone amounts to a 50% larger customer base at current valuations -- Ethereum's $28 billion total market value is catching up to Bitcoin's sector-leading $57 billion cap in a hurry.

No other cryptocurrency is worth more than $7 billion right now, but a veritable ocean of hopeful currencies adds up in a hurry. According to cryptocurrency value tracker, the total e-currency market is worth roughly $124 billion as of this writing. Bitcoin amounts to 46% of that hefty sum.

More importantly, there's always a chance that some digital currency not named bitcoin might rise up and take over as the leading solution. Each type of digital coin comes with a unique set of production rules, valuation assumptions, security solutions, and additional features. Bitcoin has the first-mover advantage but its particular mix might not win in the long run.

If so, ShapeShift would quickly help Overstock adjust to the new world order and start managing e-currency orders in some other base currency. Besides growing Overstock's potential customer base among digital currency fans, this move adds another layer of operational flexibility to the whole idea.

Pile of gold coins emblazoned with the Bitcoin logo.

Image source: The Bitcoin Foundation.

So Overstock is an obvious e-currency investment, right?

Not so fast.

The online retailer certainly could serve as an oblique way to invest in cryptocurrencies, especially since Overstock runs a service of its own that hopes to replace modern stock exchanges with a post-modern blockchain solution. The trading platform, known as t0, is a little threadbare so far with only one security offered for sale (a blockchain version of preferred shares in, of course), but Overstock CEO Patrick Byrne calls it proof that there is a place for blockchain tools in the world of stock trading.

That being said, Overstock may end up cutting its blockchain operations loose as a stand-alone and unrelated business, and the ShapeShift deal certainly doesn't look like a vote of confidence in Overstock's in-house e-currency operations. That business is still too small to break out as a separate reporting segment, so Overstock rolls it into the "other" business segment that also includes noncontrolling equity investments in other small businesses. Together, that division adds up to quarterly sales of roughly $4 million and operating losses of roughly $3.3 million.

Blockchain operations are a very small part of the Overstock business, and the company is facing many serious hurdles in the mainline e-commerce segment. The company is burning more cash than it's making, despite solid top-line revenue growth. And operating margins are erratic at best.

All things considered, the potential upside of Overstock's e-currency moves is overshadowed by the rickety nature of the much larger online shopping operation. If you insist on treating Bitcoin and other cryptocurrencies as an investment tool, there are many better ways to get into that market today.

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.