Stop me if you've heard this one before.

Rising speculation in stocks of companies with no apparent investment worth that have attracted legions of short sellers.

Soaring purchases of options, notably those that expire the same day, making them analogous to lottery tickets that cost little but offer big payoffs -- when they actually pay off.

A pervasive notion that this time is different, while stocks are at records and command historically high valuations.

Buy high and sell higher, because if you don't, you'll have fear of missing out, the dreaded FOMO syndrome.

While market-related headlines continue to focus on the major indexes, such as the S&P 500, the Nasdaq, and the Dow Jones industrials, notching records, a lot of the action has been in the so-called meme stocks -- securities with negligible investment value but that are ripe to bid up.

Speculators in this game focus on shares that have been heavily sold short -- meaning stocks that have been borrowed and sold by those who bet they will decline. An uptick in a shorted stock's price forces the short sellers to repurchase the shares. A leveraged tack would involve buying a call option -- which would give the buyer the right to buy the stock at a predetermined price for a set period -- for a fraction of the cost of the underlying shares, which amounts to another sort of lottery ticket.

To be sure, the bullish sentiment in the market has been stimulated, in part, by excitement about artificial intelligence, which is expected to transform how we work and live. The massive investment required to bring about the AI revolution, from the hardware to the providers of energy to power data centers, also augurs huge payoffs.

"Yes, AI is different this time," writes Julian Emanuel, chief market strategist at Evercore ISI. "What is not is the cycle of Greed and Fear that is a part of every market cycle. FOMO, once it appears, doesn't move stocks in a straight line, at least not in the beginning."

And he's certain the FOMO phase has arrived.

Emanuel says a surprisingly large number of veteran investors who managed money during the dot-com bubble at the turn of the century are asking him whether it's different this time. And the query isn't limited to pros, he adds.

"We recently spoke to our friend The Dentist, who quit dentistry in 1999 to trade tech stocks," he relates.

His buddy went back to dentistry in 2003, after the tech bubble burst, and swore to be a passive index investor forever more. Until now. "The Dentist in 2025 is actively trading Bitcoin, in between root canals," Emanuel writes.

He isn't alone. So-called retail traders, or individual investors, are dominating markets, especially via zero-day-to-expiration, or 0DTE, options. These contracts with the life span of a housefly are especially attractive to punters because of their low cost. More to the point, Emanuel observes, with 0DTE options, every day is a new day to make money.

That means there is no need to worry about such details as corporate earnings, interest rates, tariffs, fiscal policy, geopolitical conflicts -- the boring stuff that drives headlines. All that matters is whether you can buy something for a penny in the morning and sell it for a nickel after lunch. Long-term investing is so yesterday.

That, in so many words, is what a friend was told by his millennial son. Now, my buddy used to oversee billions for one of the nation's major financial institutions. But his kiddo said he and his friends saw this now-retired mega-money manager as hopelessly out of touch with investment markets as they racked up gains trading meme stocks, options, and cryptocurrencies.

The trading gains shouldn't be put down as just play money. David Rosenberg, the eponym of Rosenberg Research, has observed that asset-price inflation is boosting personal income and serves as a sometimes forgotten counter to higher prices, notably from tariffs. "We live in the age of meme coins stocks, and their movements exert outsized shifts in economic behavior," he wrote in a client note.

What is often overlooked is that investors don't have to cash in their chips to enjoy their winnings. Stalwart bulls who are loath to sell here, let alone pay capital-gains taxes, can instead take out margin loans, using their holdings as collateral. Such loans have climbed in lockstep with the market, and topped $1 trillion for the first time in June, according to Finra data.

One brokerage firm this past week offered its customers an attractive deal: a fixed rate of 5.95% for one year for loans of $5 million or less, and 5.45% for larger loans, which it points out is less than the interest rate on other forms of debt. It's cheap credit for that second or third home, or boat, or classic auto, or maybe to help out a kid who might be facing new, more stringent student-loan terms under the recent Big Beautiful Bill. Meanwhile, customers stay in the market, which keeps going up.

Until it doesn't, of course. But while it does, why not? Exuberance, rational or otherwise, has paid, while conservatism has not. While the likes of Kohl's, Krispy Kreme, GoPro, and Wendy's gyrate and enrich traders in these stocks and related options, Berkshire Hathaway is off about 10% from its peak in May, reached before its nonagenarian CEO, Warren Buffett, announced he would relinquish the reins at year end.

Even more imaginative than the manipulation of meme stocks are some of the financings that exploit the speculative fervor in the market. MicroStrategy, now doing business as Strategy, was back this past week with its fourth preferred stock offering, totaling $2.5 billion, in what my astute colleague, Andrew Bary, described as "a Bitcoin-backed version of U.S. Treasury bills" yielding as much as 10%. These new securities will trade under the ticker STRC, for their moniker "Stretch."

MicroStrategy originated the Bitcoin Treasury tack, in which the company puts a speculative asset such as crypto on its balance sheet instead of old, prosaic money-market instruments, and watches its stock soar. Taking the ploy a step further was Quantum BioPharma, which this past week announced a "strategic investment" in GameStop, the OG meme stock.

Even in the relatively staid credit markets, extremes are evident. Investment-grade and high-yield spreads are historically tight while esoteric structures (such as payment-in-kind securities, which pay interest in more bonds instead of cash) are staging a return. Meanwhile, private credit is expanding beyond institutional investors, who presumably can assess the risks, to individuals' retirement accounts.

These are all symptoms of market peaks, not their lows. And they're all too familiar to those who have been through multiple market cycles. But the naysayers are being left behind.