Google and Facebook: How two giants can transform the landscape in a day

It sure was fitting that Google (GOOG) killed an entire product segment on Oct. 28, just a day before the 80th anniversary of the 1929 stock market crash. And appropriately enough, on Wednesday the tech-heavy NASDAQ tumbled mightily. Contributing to that fall was the pummeling of GPS makers Garmin (GRMN) and TomTom (TMOAF), whose shares plunged 16% and 21%, respectively. TomTom shares kept falling the next day, dropping by 11% more.

That's because search giant Google unveiled what appears to be a revolutionary GPS guidance unit for smart phones running Google's Android operating system. Collectively, those two GPS companies lost more than $2 billion in market cap. Even shares of iPhone maker Apple (AAPL) fell by a startling 5%, more than retracing all the recent gains the stock had made after posting stellar earnings last week.