SAN FRANCISCO (BLOOMBERG) - When Americans gather around the Thanksgiving table this week, the blistering rally in technology, electric vehicles and crypto-related stocks is likely to be a part of their conversations.

There's a reason it will dominate the small talk: The tech-heavy Nasdaq 100 is now worth almost half as much as the benchmark S&P 500 - the highest ever - and the megacap tech stocks alone represent a third of the S&P 500.

Nvidia Corp and Roblox Corp's sprint stood out in a year when the rest of the big tech names jogged to new highs, defying several calls to sell the sector around last year's thanksgiving due to soaring valuations.

Here some of the hottest stocks and themes since last Thanksgiving:

Hot chip makers

Nvidia has soared 148 per cent as booming chip demand and a foray into the metaverse made it the best performer on the Nasdaq 100.

Applied Materials and Advanced Micro Devices were other winners, each rising about 80 per cent and outperforming many of the megacap tech stocks.

Surging EV makers

Tesla soared to a US$1 trillion market value as the electric-carmaker's shares doubled in value, driven by a sustained pickup in sales, even as part shortages were crippling the broader auto industry.

EV fever was even more evident with Rivian Automotive, which doubled in value in less than two weeks after going public. Lucid Group was the sector's other hot name.

Metaverse mania

Roblox's tripling of value from its March listing to Facebook's name change to Meta Platforms showed the metaverse was the next big thing in tech. The rush to the space was evident with the Roundhill Ball Metaverse ETF, an exchange traded fund focused on the theme, surpassing US$500 million in assets under management on Nov 17, having doubled in just two weeks.

Cryptocurrency craze

From the digital world to digital money: Bitcoin briefly reclaiming US$60,000 and a rally in smaller cryptocurrencies boosted a host of related stocks such as Marathon Digital Holdings, Riot Blockchain and MicroStrategy. Marathon Digital was among the top winners, with its stock jumping ten-fold.

Don't forget FAANGs

Retail investors who stuck with big names haven't done badly either. The likes of Microsoft , Alphabet and Tesla, have alone added a whopping US$3.5 trillion in 2021, while the NYSE FANG+ Index is up about 39 per cent since last Thanksgiving.

While those numbers are impressive, some say valuations do seem stretched. Tech stocks haven't been this expensive since the Internet bubble of the late 1990s and many investors remain cautious.

"Let's all be thankful for the tremendous returns we've seen in tech stocks and numerous other areas of the market this year, but not forget that a slice of humble pie may be what we're eating next year if we're too certain of our predictions to come," said Mr Matt Carvalho, chief investment officer of Cardinal Point Wealth.