There are a number of altcoins (SHIB, ADA, DOGE, MATIC, XRP, MTAUR) that are priced below $1 and are considered popular and interesting investments. Here is a summary of some of them:

1. Shiba Inu (SHIB):

Price: Much less than one dollar.

Features: SHIB is one of the cryptocurrencies inspired by Dogecoin and has been rapidly growing in popularity. Known as a “Dogecoin killer” and focused on community and decentralization, it has also launched projects like ShibaSwap for decentralized finance (DeFi).

2. Cardano (ADA):

Price: Usually less than $1 during weak periods.

Features: Cardano is a smart contract blockchain project, and is considered a strong competitor to Ethereum. Its network is flexible and efficient, with a great focus on scientific research and infrastructure development.

3. Dogecoin (DOGE):

Price: Usually less than $1.

Features: Dogecoin started out as a joke, but has become one of the most popular cryptocurrencies thanks to its strong community support and public figures like Elon Musk. DOGE is mainly used for tips and micropayments.

4. Polygon (MATIC):

Price: Close to a dollar, sometimes less than a dollar.

Features: MATIC is a prominent solution for scaling the Ethereum network. It is used to speed up, facilitate and make transactions on the Ethereum network less expensive.

5. XRP (Ripple):

Price: Mostly fluctuates around $0.50 - $0.70.

Features: XRP is used to facilitate fast and low-cost cross-border payments. The Ripple network is used by many large financial institutions.

6. Metaur (MTAUR):

Price: Not widely known compared to other currencies.

Features: Metaur is a relatively new cryptocurrency that may be part of a specific project or platform. It has not been as popular as other major currencies.

Why are these currencies attractive?

Cheap investment: Since these coins are priced at less than $1, they are attractive to investors looking for low-cost but potentially high-growth investment opportunities.

Active communities: Most of these coins have strong support from large communities and are involved in technology developments such as smart contracts and decentralized applications (dApps).

Practical Use: Some of these coins, such as MATIC, ADA, and XRP, have strong use cases in improving payment systems and scaling the blockchain.

If you are considering investing, it is important to monitor market analysis and research deeper into each coin and its technical and community strength.