I've heard and read about suppressed inventions for decades, such as the mythical device that you can bolt onto your car to make it run on water or instantly get 100 MPG. When actually tested (as was done on Mythbusters), these devices all turn out to be hoaxes and/or frauds. Seen another way, this could also be debunked by simple reasoning. Back in the 1970s when two events drove up the price of oil sharply (the 1973 OPEC oil embargo following the Yom Kippur War and the fall of the Shah of Iran in 1977 or 78). Gas prices doubled following each of these events. Millions of people suddenly became interested in buying more fuel efficient cars. The US automakers in the early 1970s had the Vega, the Pinto, and the Gremlin (winners all), so people started buying cars from funny sounding companies like Toyota, Honda, and Datsun (now Nissan). The US auto industry lost a lot of market share and has never regained it. At the time, GM was the biggest US corporation. I find it hard to believe that they would've willingly let their market share erode so the oil companies could make more money. If there were easy ways to increase mileage, they would've used them.

Then again, some rumored inventions don't look so good when you do a little basic math. For example: If it works as it's supposed to, it will charge up in five minutes and provide enough energy to drive 500 miles on about $9 worth of electricity.

Where I live, electricity costs about 10 cents per kilowatt hour, so $9 worth of electricity is roughly 90 kilowatt hours. To push that amount of electricity in 5 minutes, you'd need a system that would be sized to push 1080 kilowatts of electricity in an hour (90 * 12). Applying Ohm's law (Power = voltage * current), a voltage of 1080 volts would require a current of 1000 amps to carry 90 kilowatt/hours of electricity in 5 minutes. Personally, I wouldn't want to be anywhere in the area while that's going on.

If you sell someone a widget, you get the price of the widget. Once. If that person can use the widget without anyone's help, then you get nothing beyond the purchase price. But if that person needs your help using the widget, and can be persuaded to pay for that help, then you have not only the price of the widget but also the price of the support and consultation. Therefore there is a motivation in some circles to make products that are difficult to use and require ongoing support.

Which is as good an explaination for Microsoft's business plan as I've ever seen.