Every year marketing and advertising campaigns in the United States embark on monstrous spending sprees culminating in costs upward of $250 billion. And often the companies who commissioned them may have been better off opening the window and dropping the cash on the street below.

To cater to an increasingly skeptical audience that seemingly prides itself on not succumbing to standard messages, marketing creative directors at ad firms are being forced to be a bit more creative these days.  And often the best way to do that is create a campaign so far outside the traditional parameters of the medium that it’s difficult for anyone to tell whether or not it is designed to sell something. Or, the message is so creative viewers don’t mind they are being pitched.

This is where guerrilla marketing comes in. The best guerrilla marketing campaigns forego the big budgets, and instead opt for ingenuity and often a little elbow grease to target unsuspecting targets in unexpected places.

Here are five that fit the definition and got a lot of attention:

Vodafone

Hit ’em where it hurts! At a 2002 Bledisloe Cup rugby match in Australia two men streaked naked across the field during a particularly important moment of play. The duo was as naked as the day they were born except for a Vodafone logo painted on their backs.

While streakers aren’t exactly a rare phenomenon (even ones with logos painted on their backs) the gambit was particularly clever because the event was being contested at Telstra Stadium – named for Vodafone’s chief competitor.

The clever stunt was broadcast around the world and made headlines at top tier newspapers and even garnered clips on CNN.

Folgers

How many times can a company show an attractive homemaker sniffing her morning coffee from a cup? Well, Folgers has almost certainly shown that image as much as anybody in the 160 years since they started brewing beans. However, in 2010 Saatchi & Saatchi did some pretty cool guerrilla advertising for Folgers. In conjunction with a digital printing company that provided some pretty great printing solutions, the creative team at Saatchi & Saatchi turned manhole covers into cups of coffee and allowed the steam that often pours out to create a fresh brewed visual.

Greenpeace
Greenpeace Switzerland created a memorable campaign against nuclear plants when it organized a flash mob to emulate what it would look like if a nuclear cloud spread over the country.

The video, ‘The Zoning Plan,’ was viewed over 770,000 times since it was uploaded to YouTube on May, 2010.

The video is very effective.

Trimline Security Glass

Security glass is a pretty boring business. But in 2005, Canadian creative agency Rethink designed a low-budget promotion that got the whole city of Vancouver buzzing. The company built a glass-walled bus shelter with its client Trimline Security Glass and stuffed the insides with $3 million in Canadian currency. Only about $500 of the cash was real money, but the counterfeit bills underneath looked real enough to fool passersby. Soon it was the most popular bus stop in the city.

The gimmick got a front-page story in The Vancouver Sun, which described people passing by trying to break open the security glass.  The agency wisely followed posted video of the attempts on the Internet.

Not bad for the $6,000 Canadian fee.

UNICEF’s Dirty Water

A couple weeks ago during World Water Week UNICEF’s launched its “Dirty Water” campaign  by installing a vending machine in Manhattan’s Union Square filled with dirty water in various flavors – cholera, typhoid and dysentery.

The clear bottles filled with mucky water were quite effective.