(Editor's note: In an earlier version of this story, it was reported that the Fool owns shares of Best Buy. It does not own any Best Buy shares. The Fool apologizes for the error.)    

Bad days. We all have them; some of us deserve them. Here are five stocks whose naughty ways drew investors' scorn on Monday:


Closing Price

CAPS Rating (5 Max)

% Change

52-Week Range

Sycamore Networks (Nasdaq: SCMR)





RadioShack (NYSE: RSH)





Talbots (NYSE: TLB)





Travelzoo (Nasdaq: TZOO)





Microsoft (Nasdaq: MSFT)





Sources: The Wall Street Journal, Yahoo! Finance, Motley Fool CAPS.

Well, OK, we can't exactly call these stocks naughty. There are days when five-star winners and newsletter recommendations appear here. Today is one of those days.

But if you're an investor, you'll have plenty of bad days. The trick is to avoid dating -- or, worse, marrying -- your losers. That's why I listen when our 100,000-person-strong Motley Fool CAPS community of stock pickers speaks with a poor rating or a negative pitch. You should listen, too.

Thus, here is today's list of the worst stocks in the world.

We begin with Microsoft, which can't seem to decide whether it wants to be Microhoo.

Saturday, you see, was supposed to be "D-day" -- as in "deal day" -- for Microsoft and Yahoo! (Nasdaq: YHOO). Either work out a deal with us, CEO Steve Ballmer said in a terse note to Yahoo!'s board, or we'll be forced to launch a hostile bid.

So now that the deadline has passed, Mr. Softy is aggressively buying shares of Yahoo! and preparing for a proxy fight, right? Right?!? If only we knew.

Perhaps the Beatles were right: Love was an easy game for Microhoo to play in February. But now, May is nearly upon us. The flirting is old, the threats are empty, and no one's hired a wedding planner.

Come on, Mr. Softy. Your users loathe waffling as much as they hate Vista. Your shareholders like it even less.

Next up is RadioShack, which reported first-quarter earnings that beat estimates on both the top and bottom lines.

But in this case, a "beat" means "didn't implode by as much as analysts thought." Overall revenue declined 4.4%, and same-store sales -- a key indicator of retail success -- dropped 4%. Fewer people are buying less stuff, in other words.

Foolish colleague Ryan Fuhrmann says it best, I think, in a recent Fool article: "I would have to say that at this point it's caveat emptor for current and prospective shareholders, primarily because I can't see why shoppers would head to RadioShack over rivals like Best Buy, Wal-Mart  (NYSE: WMT), or even embattled Circuit City. These category killers sell a much wider array of goods, and many times at a more competitive price."

Buy this stock, or take a poke in the eye with a sharp stick? I'll take the sharp stick, thanks. It'll hurt less.

But our winner is Sycamore Networks, which said on Monday that its third-quarter revenue would be roughly $21 million, resulting in a better than 50% year-over-year decline. A major customer apparently didn't order as much as executives had expected, Sycamore said in a company (under)statement.

Oh, don't look so surprised. Sycamore made it plain in its most recent 10-Q filing that its fortunes are tied to a very few patrons:

For the three months ended January 26, 2008, we had two customers who contributed 10% or more of our total revenue. ... We expect future revenue will continue to be highly concentrated in a relatively small number of customers. ... The loss of any one of these customers or any substantial reduction or delay in orders by any one of these customers could materially and adversely affect our business, financial condition and results of operations. [Emphasis added.]

Adversely affect? How about obliterate? Obviously, Sycamore's major customers account for far more than 10% of revenue on a rolling basis.

Sycamore Networks and its concentrated cadre of credit-crunched customers ... Monday's worst stock in the CAPS world.

Do you agree? Disagree? Let us know what you think by signing up for CAPS today. It's 100% free to participate.

I'll be back tomorrow with more stock horror stories.

Best Buy, Microsoft, and Wal-Mart are all Inside Value picks. Take a guest pass to the service to get 30 days of free, unfettered access to the team's research and recommendations. There's no obligation to subscribe.

Fool contributor and Rule Breakers writer Tim Beyers, who is ranked 12,433 out of more than 100,000 participants in CAPS, hopes that Keith Olbermann doesn't mind the blatant theft of his "Worst Person in the World" segment from Countdown. Remember, Keith, imitation is the sincerest form of flattery. Tim didn't own shares in any of the companies mentioned in this article at the time of publication. Best Buy is a Stock Advisor pick. The Fool's disclosure policy thinks cooked spinach is the worst veggie in the world.