These days, wireless mice and keyboards are so inexpensive that they're showing up everywhere -- even in large corporate purchases for every desk in the enterprise. Unfortunately, most wireless keyboards have an Achilles Heel which render them dangerous to your security: Key presses are sent "in the clear" to your PC, so anyone with the right surveillance hardware can actually record every keystroke you make from a distance.
Is this a serious problem? Potentially. It sounds far-fetched, like the plot to a science fiction movie, but it's actually quite easy to monitor wireless peripherals and is one way to capture private and corporate data.
The solution is here: Microsoft's Wireless Desktop 2000 uses 128-bit AES encryption to ensure what you type protected.
Like most of Microsoft's peripherals, this one uses BlueTrack wireless technology. It sells for about $40; It's certainly not the first encrypted wireless keyboard, but it appears to be the least expensive model I have found.
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