American companies have spent hundreds of thousands of dollars to create humorous online videos in hopes they’ll go “viral” — what it’s called when Internet users spread content via blogs, e-mails, 140-character tweets and reach millions of viewers, without the hefty placement fees to media companies.

Their Chinese counterparts have also followed this trend. While Chinese media planners still focus on primetime ads in mainstream TV networks, we’ve also seen some really smart viral video campaigns from local companies in recent years. Here three of the best video ads especially made for the online community.

Have You Abandoned Your CDMA Phones?

In the summer of 2004, China Mobile and China Unicom were locked in a battle over wireless standards. While China Unicom kept implying their CDMA standard worked much better and provided much stronger signal than what China Mobile’s GPRS could do, the video clip above was indeed a bitch slap to China Unicom’s face.

The editors seamlessly mixed clips from different blockbuster together and dubbed them into Chinese. Even though no one has claimed responsibility for this clip, most Chinese Internet users still believe China Mobile was the master mind beneath and this is the smartest Chinese viral video ad ever.

Baidu Knows Chinese Better

This ad was made in the summer of 2005, weeks before Baidu’s IPO. Even without any video-sharing website back then, you could receive links point to the download address of this video clip several times a day via MSN Messenger and QQ.

In this clip, Tang Bohu (唐伯虎), a historical Chinese playboy poet, punctuates the long sentence “I know you don’t know I know you don’t know I know you don’t know” (我知道你不知道我知道你不知道我知道你不知道)  three times and gives it three totally different meanings. Meanwhile, the hapless foreigner can only respond nothing but “I know” (我知道) in all wrong tones.

Although this ad didn’t mention Google in the vid, it seems pretty obvious that Google, the only competitor of Baidu in China, was represented by the foreigner.

MC Farmer: The Real Origin of Hip-Hop

I’ll bet you didn’t know that scratching, the technique of moving a vinyl record back and forth on a turntable, was invented by a farmer in northwestern China totally by accident, and the spirit of hip-hop dance comes from chickens and cows in fact - you will find the real origin of hip-hop music in this viral video.

This ad was made by the end of 2007 to promote the “cool” factor of Nokia’s N-series cell phones. Though there’s a lot of Chinese dialogue with a very strong regional accent, you can easily understand it without English subtitle.

Earlier this month, Nokia marketing executives from all around the globe watched this video on Youku.com together in their Beijing headquarter, and they burst into laughter without any explanation.