(Bloomberg) -- Earlier this month, an image of a pet rock sold for the equivalent of more than $200,000 in the non-fungible token market.

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Meanwhile, the market capitalization of a cryptocurrency called Pepe — a meme coin based on a cartoon frog — doubled in just a few weeks. And even the price of the FTT token, which was created by the FTX exchange and currently has no real utility, has tripled in the past month on hopes that Sam Bankman-Fried’s exchange will return from the dead.

Everywhere you look, there are signs that the wacky excesses of the crypto market — and fear of missing out on them — are making an unlikely comeback. As expectations of an imminent approval of a spot-Bitcoin exchange-traded fund pushes the oldest and biggest cryptocurrency ever higher, the hype has also lifted other boats — even those considered among the least seaworthy.

This latest rise of digital junk follows a nearly two-year long crypto winter that saw the value of thousands of dubious projects slide — some to nearly zero — to the delight of critics and even some industry insiders. Aggressive actions by the Securities and Exchange Commission marked some crypto coins as illegal and chased some promoters away from crypto. Now it appears that the cleansing was only been temporary.

“As prices rise, investors on the sidelines think they need to get in,” said Campbell Harvey, a finance professor at Duke University. “Many will violate the number-one rule of investment: Understand what you are investing in. Many will also violate the number-two rule by putting their money in an undiversified bet on a single token.”

Social media is once again full of posts hyping meme coins. One of them is simply called Memecoin, which was created earlier this year and has shot up in value this month. Its short whitepaper, where disclaimers take up about as much space as explanations, notes that the token “has no functions, no utility and no intrinsic value, no promise or expectation of any financial return, profit, interest or dividend.”

“Looking for a new theme to rake in customer money for no value — that’s the theme in non-Bitcoin crypto,” Cory Klippsten, chief executive of Bitcoin services provider Swan, said in an interview. “I guarantee there will be another hype cycle for alt coins, and more people will get hurt.”

Static images of rocks tied to the Ethereum and Bitcoin blockchains are selling for eye-popping prices again. Bitcoin Rock #75 recently sold for almost three Bitcoin, or about $112,900. The collection, like many others, is held by a small group of people. And like most NFT collections, the rocks aren’t very liquid. Meanwhile, a slew of projects are holding NFT land sales — effectively selling NFTs of properties inside digital territories of games — even though many participants in prior-generation projects got burned.

“It’s important to note the current climate of what might be described as a mini bull market,” said Sara Gherghelas, an analyst at researcher DappRadar. “This environment has infused the NFT space with a fresh wave of enthusiasm and speculative investment, which can sometimes inflate the prices of projects that might otherwise have limited long-term value.”

TG Casino, focused on offering anonymous crypto gambling on Telegram, has raised more than $2 million in a token pre-sale, which includes selling NFTs to high rollers. In years past, people’s investments into many token sales crashed and burned.

Amid the frenetic rush into the latest hot token, some buyers end up being what’s known as rug-pulled — or duped by scams in which the coin’s creators disappear along with liquidity. In the third quarter, rug pulls accounted for 65.1% of all types of attacks in crypto, according to blockchain security auditor Hacken.io.

“Optimists are seeing thaws in the crypto winter, and even green shoots,” said Aaron Brown, a crypto investor who writes for Bloomberg Opinion. “If this really is early crypto spring, the good new ideas should suck the attention from the nonsense. If not, the junk should fade back to obscurity.”

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