We are entering one of those fascinating times in the quarter where most big companies have reported earnings, so market participants tend think about what they have learned and plot their next moves. 

At the same time, there are still important companies that have not yet reported results, and they have an opportunity to surprise, frustrate and delight the crowd. Last week, one of them, Dell (NASDAQ:DELL), did just that.

On the same afternoon came a buyout offer for one of my longtime recommendations, Family Dollar (NYSE:FDO) at a 25% premium — a move that speaks volumes about where we are in the cycle.

First let’s check out Dell. For those of you not trading in the 1990s, you just need to know that the Texas tech giant was one of the most amazing stocks of all time to own, trade, watch, think about, obsess over, and mostly make tons and tons of money from. Its founder and managers were the first to figure out how to mass produce the most important consumer and business tool ever invented, the personal computer, and reaped the bounty.

Here’s something you probably won’t believe, but the truth is in the fine print: from Jan 5., 1990 to Dec. 31, 1999, Dell shares rose 88,750%, or enough to turn a $10,000 investment into roughly $8.9 million. 

The term “Dellioniare” was coined to describe the yuppy sales and product managers that roared up and down Austin, Texas, streets back then in their Ferraris. Virtually every quarter presented an opportunity for the average trader anywhere in the world to make a fortune on Dell calls. It was like a dream.

In the 2000s, though, came heartbreak. Every other PC company caught up with Dell, and its managers made one mistake after another as their market matured. In recent years it became a sad shell of its former self — still large, but more fat and dopey than muscular and brilliant.

Fast forward to its earnings report last week: It was a barn-burner, completely blowing apart the markets’ skeptical attitude toward this once-great, and perhaps soon-to-be-great-again, goliath. Dell reported earnings of 53 cents a share after extraordinary items, vs. the consensus expectation of 37 cents a share. Sales came in a touch lighter than expected, but margins were incredible: 21.5%, vs. the consensus of 18.7% gross margins, and 8.2% operating margins vs. consensus at 6.4%.

These kinds of surprises are what market junkies live for because they shatter the paradigm of thinking about a company that has reigned, in this case, for half a decade. Dell has been trying to shrug off the weight of its legacy personal computer business — a dead-end in the era of the mobile workforce — and reinvent itself as a software services and storage specialist.

Pundits have been leery and investors have been skeptical. And yet that is what Dell has apparently managed to do. In a statement, managers guided 2012 earnings and sales up by almost double what the Street expected.

It’s been so sad in a way, as we have discussed before, to see how badly Microsoft (NASDAQ:MSFT), Intel (NASDAQ:INTC), Cisco (NASDAQ:CSCO) and Dell have blown the opportunities presented by the mobile Internet. 

Oracle (NASDAQ:ORCL) was the only one of the Fearsome Fivesome of the 1990s that figured out early and often how to survive in the new world. IBM (NYSE:IBM), a much more mature company that had lost its way earlier, also figured it out. Hewlett-Packard (NYSE:HPQ), despite horrendous management missteps from time to time, finally figured it out, too. And now maybe, just maybe, Dell has come around. 

Its founder and executives are proud men and women, and they were so embarrassed by their mistakes of the past that they have put a lot of effort into getting the next phase of their business right. I would love to see them right the ship and pull an IBM here: Yank the stick back, steer out of their long decline and ascend back toward where they were at least in the mid-2000s. The stock is cheap, management is buying back shares, and they are on the right track with their new focus on services and storage.

Now here’s the why the company is gaining ground, and it’s important for all of tech — Dell’s fourth-quarter recovery manifested a sharp rebound in business spending on technology. The company said sales to large companies jumped 12% to $4.7 billion in the fourth quarter compared with the period a year ago. Among small- and medium-sized businesses, sales rose 12% to $3.7 billion. 

Dell continued to struggle with consumers, a division where sales fell 8% to $3.3 billion. That is a shame because this is the space in which Apple (NASDAQ:AAPL) has won big. But Dell has come to recognize it does not have a good touch with consumers, and that is why it is refocusing on business customers.

This is the strategy that IBM pursued when it dumped its consumer PC division to Lenovo, and it is probably smart. Just like people, companies need to recognize that they can’t do everything equally well. As the Most Interesting Man in the World says in the Dos Equis commercials, “Find out what you don’t do well, and don’t do that thing.”

My expectation is that Dell can regain its mojo. No one ever thought IBM would get its groove back. No one ever thought H-P would rebound. No one ever thought that Verizon (NYSE:VZ), which hit a new all-time high this week, would either. Surprises happen. That’s what makes this game fun. Dell is not completely out of the woods yet. But it is getting there. Ding-dong. It’s time again for Dell.

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