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. Instant weight loss at Starbucks
Starbucks (NASDAQ:SBUX) is so confident about the quality of its new VIA instant coffee that it's offering Canadian java junkies the chance to sample VIA packets in hot water alongside its signature brews.

The taste test is gutsy. Starbucks is not only competing against itself, but also hoping to persuade customers that a $1 pack of instant bean juice can match up to its slightly more expensive in-store coffee.

I can understand that Starbucks wants to set the bar high for VIA. There's a growing market for premium coffee beyond barista-brewed offerings, and Starbucks wants a little more skin in that game. However, it could have pitted itself against other coffeehouse chains or instant coffee marketers, rather than taking aim at its own heart.

2. More bling than Bing
I hope Microsoft (NASDAQ:MSFT) enjoyed its summer of cockiness. Web analytics firm StatCounter is reporting that Bing's market share fell significantly in September, after gaining ground every month since its springtime launch.

StatCounter's numbers show Bing commanding 8.51% of the search engine market in September, after peaking at 9.64% a month earlier. That slick "decision engine" interface and brash marketing campaign seemed so effective this summer.

Did Bing try too hard? Did it jump the shark when it announced that Bing would power results of rival Yahoo! (NASDAQ:YHOO) in late July? The move was originally portrayed as a victory for Microsoft, but it may have eventually convinced cynical users that Microsoft was out to corner the search market the way it dominates in operating systems, Web browsers, and productivity applications.

3. Get lost, Garmin
After nearly two years of dancing around its nuvifone promise, Garmin (NASDAQ:GRMN) finally came clean with details for its first GPS-minded smartphone.

The bad news? Garmin is going with AT&T (NYSE:T) as its exclusive provider. Doesn't it realize that AT&T is tied to the iPhone and its rudimentary GPS navigational features? Hasn't it heard about the struggling AT&T network, given Ma Bell's inability to handle the data onslaught of smartphones? If folks will be tapping the Web for Garmin routing and traffic updates, AT&T may not be the place to be right now.

Sadly, in the time that Garmin has taken to bring the nuviphone to market, the number of rival smartphone users locked into two-year contracts has grown by tens of millions.

You're too late, Garmin. Judging by the carrier you chose, you're also at the wrong place at the wrong time. For a navigation company, that seems particularly ironic.

4. It's missing that new-car smell
Have you seen those gutsy General Motors ads, offering buyers their money back within 60 days if they don't "absolutely love" their new GM purchases? Well, it seems as if GM can also play the dissatisfaction card. The distressed automaker is ending its listing experiment with eBay (NASDAQ:EBAY) just two months into the arrangement.

GM was working with dozens of West Coast dealers, hoping that listing new cars on eBay would generate worthwhile leads. Neither company is coughing up specifics, but the experiment obviously isn't working, given its premature axing.

Couldn't GM have waited to throw in the towel until more of the 2010 models hit the showrooms, and the "cash for clunkers" confusion subsides?

5. You've got fail
It's hard to decide which is fading faster at AOL these days: its access subscribers, or its valuation. A pair of analyst reports peg the value of Time Warner's (NYSE:TWX) online arm at $4 billion and $4.2 billion, respectively.

AOL once commanded a market cap of $180 billion at the peak of the dot-com bubble. A few years after the bust, the world's leading search engine, Google, was still willing to make a $1 billion investment for a 5% sliver of AOL, valuing America Online at a still-respectable $20 billion.

Now it's down to $4 billion? Really? Time Warner blew it by not unloading AOL earlier. However, now that AOL has savvy management in place, and the tech economy appears to have bottomed out, Time Warner appears ready to compound its earlier mistake by cashing out of AOL at the bottom.

Let's beat the dumb drum: