Google AdSense has served as the fuel that drives many Web content sites. But rely too much on one vendor for your revenues and you could find yourself in trouble.

That's the lesson one Israeli company, IncrediMail, learned when Google "disabled" its AdSense account, resulting in an overnight 40% drop in the public company's stock price. Read more about it on TechCrunch.

It's not clear what happened, but speculation includes charges of spyware-bombing and potential violations of the AdSense terms of service.

Lesson learned for small businesses: Google AdSense might be easy, but many different vehicles now exist -- from CPM banners to CPC text ads to affiliate network links and more -- to monetize your smartbiz Web site.

Google sure seems stingy of late. Blog reports recently proliferated that the company had drastically cuts the fees it pays affiliates for encouraging others to sign-up for AdSense and even totally eliminated the program for sites outside of the U.S., Canada and Japan, leading ProBlogger.net to write a breaking up with Google.

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