What can the most successful survivors of 2001's dot-com bubble teach us about online business? In this final installment of our series on the top 100 websites of 1999 (as compiled by the now-defunct POV Magazine), we look at the wiliest survivors to see what made them winners.

Maybe the most surprising fact about this look back is that, despite the financial carnage wrought by the 2001 market crash, nearly half of 1999's top 100 sites are still around. Four of them are on today's top 10 list, as ranked by Alexa: Google (GOOGL 1.50%), Yahoo! (NASDAQ: YHOO), Amazon.com (AMZN 0.92%), and eBay (EBAY 0.82%). And all of the thriving survivors, whether they deal in box scores, stock market news, books, or vintage treasures from some guy's attic, understand what people in the developed world generally want: shopping, entertainment (including sports), and information.

People want stuff, knowledge, and fun

All of the sites that made the 1999 list and are thriving today offer information, entertainment, shopping or some combination of those three elements—the same things people were interested in before the Internet was integrated into our daily lives.

They sell everything -- or something specific and highly desirable

Amazon and eBay, of course, serve up unparalleled selections of items so there's something for just about every shopper. But designer-clothing discounter Bluefly successfully navigated the crash, too. Bluefly serves a specialized market of label-conscious bargain hunters who don't mind paying a couple of thousand dollars for a Prada handbag, but would prefer to pay a few hundred less. And because, as we saw earlier, a cool idea (online auctions! online book-buying!) isn't enough, Amazon and eBay have added ever-expanding lines of merchandise, partnerships with retailers and brands, and who knows—maybe deliveries by drones.

They help people get smarter, especially about money

Information is its own form of currency, and sites that make useful information easy to find tend to do well. See Google and Yahoo, veterans of the search-engine shakeout. And within the general field of information, two categories stand out: news and money.

Of the 1999 survivors, six of the most successful focus on money. The Motley Fool, The Street.com, the Wall Street Journal's site, Morningstar, eTrade, and Consumer Reports all serve their visitors with the knowledge to make better decisions about investing, business decisions, purchases, and personal finance, among other topics.

Another half dozen sites that made it past the wreckage of 2001 report and analyze current events: the New York Times, MSNBC, Slate, Salon, CNET, and CNN (although CNN made the list in '99 for its sports-coverage partnership with Sports Illustrated. More on sports in a bit.)

Bottom line: People like to know what's going on and they really like to learn about money.

They keep people entertained

ESPN, CBS Sports, SI.com, PBS.org, and eMusic all survived then and are popular now. eMusic's focus on hard-to-find, vintage, and global artists has earned it a loyal following among hipsters and world music aficionados. Existing sports coverage and long-running popular programs helped the three networks and Sports Illustrated magazine build successful long-term presences online. (Smaller players abounded before the crash, but as we saw with old-media companies buying Internet upstarts, it's easier to add a new distribution channel than to build a channel's worth on content from scratch.)

Winning sites mix it up

Shopping, information, and entertainment don't exist as separate categories, of course. eMusic blends its album and single inventory with interviews and reviews. Bidding in an eBay auction or submitting a plane fare bid to Priceline is its own sort of thrill. And sports sites have gone in for fantasy sports leagues in a big way.

The real lesson of the dot-com bubble

In 1999, there was a lot of gee-whiz reporting about how the Internet would revolutionize our lives. And it did, in very real ways.

But it didn't fundamentally alter human nature. Most of us didn't become content producers or reach out to people around the world on our own when the World Wide Web was young. We waited for Facebook and Twitter to hand those capabilities to us on a platter. Even now, most of us use these powerful platforms to chat about our daily lives with friends and family—and to play Candy Crush.

We may be shopping on our phones instead of driving to the mall, or looking up recipes on Epicurious (another dot-com bubble survivor) instead of in a file box. And my son says kids don't try to sneak into R-rated movies anymore "because streaming video, duh." But we still like shopping, knowing what's going on, and being entertained.

The hardiest survivors of the dot-com bubble understand that human nature is what it is, and they cater to it through whatever channels get the job done.