Leading digital currency Bitcoin (CRYPTO:BTC) fell as much as 18.6% in the space of 70 minutes last night. Still, the grandfather of cryptocurrencies trades no more than 30% below its all-time highs and has gained 50% in 52 weeks. Bitcoin's market cap is a massive $907 billion today. Only five companies on the stock market can boast a higher market value.

If you are interested in the cryptocurrency space but worried that Bitcoin might be flying too close to the sun, you have plenty of lower-priced options. Here's why you should consider Polkadot (CRYPTO:DOT) and Theta (CRYPTO:THETA) instead.

Digital rendering of links in a chain, where each link consists of digital data.

Image source: Getty Images.

Nuts and bolts for a thriving blockchain-based ecosystem

Anders Bylund (Polkadot): The cryptocurrency market is still in the early stages. With so much history left unwritten, it's difficult to predict which of the many thousand digital coins and tokens might survive in the long run. Therefore, I prefer to stick with the nuts-and-bolts infrastructure of the evolving market. On that note, Polkadot looks like a big long-term winner.

On this fine Saturday morning, after a marketwide price correction across every digital asset, Polkadot is changing hands at $28.32 per token. That's more than 43% below the all-time high of $50 that was set in early November. Polkadot has done nothing to deserve this dramatic haircut. The token is only moving forward toward full functionality as we speak, executing the fourth in a long series of parachain slot auctions. Parachains are a crucial part of the Polkadot network's ecosystem, allowing the winning projects to fund and launch their smart contract services with widespread popular support and access to connections with other leading cryptocurrencies.

The first winner was decentralized finance protocol Acala, raising $1.3 billion from 81,000 different Polkadot token holders. Acala already calls itself "Polkadot's economic hub," aiming to build a fully functional decentralized finance platform with its own stablecoin, dividend-like staking processes, and a highly scalable backbone based on Polkadot's blockchain system and Ethereum (CRYPTO:ETH) compatible contracts.

Next, the Moonbeam project raised $1.4 billion from more than 200,000 auction participants. Moonbeam starts with the basic Ethereum toolkit, adds Polkadot's connectivity to other blockchains, and extends the resulting platform with innovative app-building features. In the long run, this project wants to simplify the way app developers build software using smart contract features from many different blockchain systems.

The third winner, a Japanese distributed app hub named Astar Network, collected $360 million in crowdfunding from 27,100 contributions. This project reminds me of Moonbeam but also supports advanced features like the Ethereum virtual machine and layer 2 scalability boosters.

That's just the first three winners out of roughly 100 expected parachain auctions running over the next three months. Polkadot is building an impressive portfolio of developer-friendly technologies here. The resulting ecosystem should be a robust and flexible entity with long-term staying power. Yet, market forces have driven Polkadot's prices much lower even as the network and token are moving toward this promising future.

So Polkadot is one of my favorite cryptocurrencies right now, especially when you can pick up tokens at dramatically lower prices.

A robotic hand holds a ball of video images, surrounded by digital numbers.

Image source: Getty Images.

This cryptocurrency has some great fundamentals

Bram Berkowitz (Theta): I was surprised that Theta (CRYPTO:THETA) remained around its recent price level of $6.50 for so long, despite having so much going for it. Even after Saturday's sudden 23% drop, the token still trades for just $5. One of the things that crypto investors look for is good real-world utility because there are now so many cryptocurrencies that can transmit money. Theta has a tremendous use case as a blockchain that enables peer-to-peer video streaming, with the goal of improving the quality of expensive video streaming in a more cost-efficient manner. The network does this by allowing people to share bandwidth from their own devices when they are not using them in order to ease congestion on the standard content delivery networks that companies build to support streaming. Users that extend their bandwidth to the network can get tokens and earn money.

Theta has obtained high-level advisors and support from big names like Steve Chen, co-founder of YouTube, and Justin Kan, co-founder of Twitch. It has also added big companies to serve as enterprise validator nodes, which help run the network, like Alphabet's Google, Sony, Samsung, and CAA. Theta has obtained six different patents to protect its technology and further boost its competitive advantage.

Theta at one point traded for as high as $14 but has since failed to gain much traction. Still, it has several characteristics that might make it attractive for crypto investors. For one, the supply of Theta tokens is capped at $1 billion, so there is a scarcity factor. Also, Theta is somewhat difficult to buy because it's not currently offered on a lot of the mainstream crypto exchanges like Coinbase. This likely shuts out a lot of investors that might be interested. There has been talk in the past that popular exchanges will one day offer the token to their customers, which I believe would significantly increase trading volume and likely boost the price. Theta currently has a market cap of about $5.6 billion. In comparison, Dogecoin, which I think Theta is much better than, has a more than $26 billion market cap.

Whether you prefer Polkadot's bustling app development ecosystem or Theta's video-streaming functionality, these tokens offer promising long-term value at affordable prices. Bitcoin is not the only game in town for cryptocurrency investors.

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.