Jason Calacanis, the mop-haired founder of Mahalo, an overfunded Web directory, is musing on Twitter about "tickers and rallies past" — a Proustian substitution of stock markets for madeleines. But what, exactly, does he have to be nostalgic for?

If there is a Web 2.0 bubble, it is surely in microblogging, a field popularized by Twitter.. Countless startups are thriving on the myth that sharing yourself online is too hard. Pownce cofounder Leah Culver graces the cover of MIT's alumni magazine. San Francisco's most self-involved Webheads can't stop gabbing about FriendFeed, which, as our intern Alaska Miller smartly explained to his mother, is a place where people who are really obsessed with the Internet can talk to others of like mind. And then there's Plurk, the much-mocked Twitter clone, which has drawn such derision that Web hipsters made up a company and claimed it had bought Plurk.

CollegeHumor cofounder Ricky Van Veen has decided to short the word "douche."

Most venture capitalists are adept followers of the herd. As such, their investments are best seen as trailing indicators — the financial detritus of events past, rather than predictors of what to come. Is there a bubble in Web startups? The numbers themselves are as confused as investors. Dow Jones says the first quarter saw a record $1.58 billion in venture capital invested in Internet companies. Thomson Reuters says its figure of $1.3 billion was down 7 percent from the fourth quarter. Data about VC investments is hard to obtain, and the two categorize companies differently. Anecdotally, it's clear that smart VCs have stopped funding every new social-media website and online-ad network that cross their desks. But the Valley remains awash in dumb money that has yet to be called home. The popping of this bubble will take more than a quarter's time.

Attention, Valley of the Heart's Delight: There's bad news in theNew York Times. The bullet points:

Are we in a bubble? Far too late to be asking that question, says Chris Nolan, a former Valley newspaper gossip who now runs a startup, Spot-On. She weighs in on the current market crisis and its effects on the tech business. Her thesis: New regulations will on investment banks will bring an end to the tech-stock bubbles on which Valley VCs have feasted. (I asked if this meant she was back in the tech-gossip game; Nolan's column served as one of this website's inspirations. "I'm writing about business and politics," she demurred.) Nolan compares sketchy mortgages approved by banks to the wafer-thin startups taken public by stockbrokers a decade ago. A brief version of her 887-word argument, followed by my take on where Nolan goes wrong:

SuperPoke is worth $13 million according to Facebook application tracker Adonomics. The site awards applications like Slide's Top Friends and RockYou's SuperWall values in the tens of millions of dollars — which provides some of the basis for the 9-digit figures that Slide has commanded, and RockYou hopes to get, in venture capitalists' estimates of their worth. Adonomics' numbers are as sketchy as those valuations, however. Facebook's homegrown Video application only has 807 active users, according to Adonomics stats. Something's off here, and I don't think it's just Facebook's $15 billion value.

Fortune magazine, ever servile, provides a ready platform for the powerful with something to say. The latest on stage: Jim Breyer, the Accel Partners VC with a seat on Facebook's board. Breyer has a fair point: We may be seeing the cyclical bursting of another Silicon Valley bubble. Breyer says this happens once every seven years, roughly. But his timing is suspicious. Last October, Breyer gladly took Microsoft's bubbly $240 million for a microscopic stake in Facebook. Declaring the bursting of a bubble now may help hasten its advent, and in the process, make it harder for Facebook's rivals to raise money. But for Fortune readers' tech-stock portfolios, an early warning might have been more useful. Why didn't the magazine ring him up last fall? Fortune never mentions this. (Illustration by Sean McCabe for Fortune)

"There is no bubble in technology," said Facebook board member Peter Thiel in December. Tell that to investors who bought into VMware's IPO. [VMW]

Eight years ago today, on March 10, 2000, the Nasdaq closed at 5,048.62, an all-time high. Then the bubble burst, Marketwatch notes. By October 2002, the Nasdaq was down to 1,114.11, a 78 percent drop in less than three painful years. In fact, we're still not over it. Check out the chart. The Nasdaq today stands 56 percent lower than 2000's bubbly high-water mark.

Behold the best tech ad in Super Bowl history: Apple's "1984" ad, which cost $1.6 million to make and run, and only aired nationally once. The following nine ads, while perhaps not as iconic, are all fascinating in how they seek to make the mysteries of tech compelling to the masses.

Fed chairman Ben Bernanke made a couple of moves to infuse banks with more cash before the market opened this morning. According to the Wall Street Journal, Bernanke said the Fed would hold auctions to provide funds to banks and establish foreign exchange swap lines with other central banks. The idea was to loosen up the credit market. Maybe expand some of those straitened tech budgets we warned about yesterday. Right. We think. OK, so we don't know what this move means either. But tech stocks soared on the news, so who cares? Thanks, guy in D.C.! Big movers: HP, IBM, Google, Apple, Intel, Amazon.com and Research In Motion. (Photo by David Prior)

Wall Street analysts and Sand Hill Road's moneymen have pitched tech stocks as a safe haven amidst the credit crisis. Perhaps not. While tech spending continues to outpace inflation, which is running around 2.1 percent, growth may have peaked this year at 6.9 percent. Next year may see growth fall by a percentage point or more. Here's the chart, as well as more anecdotal evidence compiled by the Wall Street Journal.

About $40 billion will go into venture capital this year and recently IPO'd stocks are up 20 percent since June. But Paul Wick of J&W Seligman, which the Financial Times calls "one of the biggest specialist tech mutual fund investors," still isn't happy about the big, special tech market. He told an audience at Venture Summit West that he blames sell-side analysts for not telling investors when to cash out on bubbly valuations.

Startup investor Peter Thiel warns CNBC's Maria Bartiromo that the current economic situation is dire. Inflation, economic bubble, deflation, blah, blah, blah. But unsurprisingly, the former PayPal CEO turned venture capitalist sees one bright spot: Facebook, the social network where, uncoincidentally, he's a board member. According to Thiel, "it's the one part [of the economy] where there is no bubble at all." Sure, Peter, as if we really needed the disclaimer you add: "Of course, I'm biased." Not even the well-trained Maria "Money Honey" Bartiromo could keep a straight face at that.

Since we first covered an eBay auction for a Facebook application on September 27 when Michael Zhang auctioned off LogBook for $2,550, the going price for useless applications has boomed nearly 280 percent, to judge by a similar sale yesterday. Then again, the I Am Hungry application sold for an even bubblier $20,100 in October. No wonder Facebook apologists more juiced?

The irrational exuberance of Pets.com, which burned through $50 million in venture capital in nine short months, will no doubt be told as a cautionary tale to our children around the campfire. What other investments are scary enough to give venture capitalists nightmares? Venture Beat has helpfully condensed Inside CRM's list of the 20 worst offenders, which includes notorious failures like Web currency Flooz and Amp'd Mobile. [VentureBeat]

ComScore reports that October 2007 retail e-commerce increased 19 percent over the same month in 2006. Sounds healthy, until you look at the year-to-date numbers through September, which had 2007 on track for 21 percent growth. October sales are usually a leading indicator for how e-commerce fares during the holidays, so the slowing growth rate isn't good. What's the cause? The usual suspects: increasing mortgages and gas prices coupled with a decline in housing values. Just so long as I get my iPhone for Christmas, whatevs. Here's the gory chart if you're that kind of masochist.

If you bought some Apple stock yesterday after its five-day, 20-percent drop, you've made out quite well. AAPL is up 11 percent today — lifting the rest of Nasdaq up with it.