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Not on the Internet, but here in the UK BMW have a tradition of running some pretty good April fools print ads - full page spreads in the reputable papers. In the past they've had the new 3 series that connects to your oven so you can start cooking your dinner as you leave work and have it ready and waiting for you when you get home; and the introduction of a new model that, to help drivers that travel between different European countries where you drive on different sides of the road, doesn't have a steering wheel and instead is controlled from either front seat using gestures and waving your arms (although it requires the passengers to sit very still to prevent accidents).

This year they are taking on Nike+iPod...
http://www.nickburcher.com/2012/04/bmw-april-fools-day-2012-ad-bmw.html
 
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