Stupidity is contagious. It gets us all from time to time. Even respectable companies can catch it. As I do every week, let's take a look at five dumb financial events this week that may make your head spin.

1. Stop being a sore loser, Michael
Some folks just can't own up to their tactical mistakes.

Dell (Nasdaq: DELL) has been slow to the netbook party. Its half-hearted efforts found it surrendering market share to Asia's Acer and ASUS during last year's holiday run, and the miniature laptops keep coming.

However, instead of making up for lost time or trying to stay one step ahead of the trend, Dell is primarily sticking to its line of larger portable computers and badmouthing the form factor of netbooks.

"If you take a user who's used to a 14- or 15-inch notebook and you say, 'Here's a 10-inch netbook,' they're gonna say, 'Hey, this is so fantastic. It's so cute. It's so light. I love it,'" CEO Michael Dell told Silicon Valley's Churchill Club on Tuesday, as retold by The Register. "But about 36 hours later, they're saying 'The screen's gonna have to go. Give me my 15-inch screen back."

So Dell is offering a very limited number of netbooks because it thinks the lovefest will die in a day and a half? We're already a year into those "36 hours," Michael. Where's the fade? Where's the return to your chunkier laptops? Even wireless handset makers are entering the netbook space.

The only thing worse than being late is being stupid about being late.

2. Danger is Microsoft's middle name         
Deutsche Telekom 's (NYSE: DT) T-Mobile is taking a kick to the sidesover its Sidekick devices. After experiencing spotty network outages, many Sidekick owners found that their server-stored contact, photo, and other media files stored on the cloud of Microsoft 's (Nasdaq: MSFT) Danger subsidiary were simply gone.

As of yesterday, Microsoft claims to have recovered "most, if not all" of the data lost in the fiasco. The one thing that won't be erased by T-Mobile is Microsoft's system failure that somehow took out both the core database and the backup.

And you thought Microsoft's nerds were smarter than that.

3. Will the real analyst please stand up
Analysts aren't supposed to nod in agreement, like a pair of football officials conferring before signaling whether the field goal attempt was good. But you also don't expect two Wall Street pros to be polar oppositesa trading day apart.

Baidu (Nasdaq: BIDU) hit a new 52-week high a week ago today, propelled by a pair of positive Wall Street notes. Citi's analyst concluded that the company will "surprise with strong results showing accelerating growth over the next 12 months."

Deutsche Bank analyst Alan Hellawell went the other way this Monday, by downgrading the stock after his check of Chinese ad brokers and consultants led him to believe that Baidu will come in at the lower end of its guidance.

They can't both be right, and when Baidu reports in a few weeks, one of these two analysts is going to have some serious egg on his face. Continued...