If you’re still feel not fast enough for input data into your PDA even using the “Auto complete input - Quick Write 5″, then this Virtual Laser Keyboard will meet your satisfactions. (What? Post about keyboard again? Ha! 
ya, this one is more Hi-Tech compare to Donya Foldable Keyboard, Full Metal keyboard or Daskeyboard) Click picture for animation demo.
Use the VKB (Virtual PC Keyboard) with both your laptop and PC and with a compatible mobile device, be it a Smartphone or a PDA. It uses both infrared and laser technology to produce an invisible circuit and project a full-size virtual QWERTY keyboard onto any surface. The virtual PC keyboard behaves exactly like a real one: direction technology based on optical recognition enables the user to tap the images of the keys, complete with realistic tapping sounds(!), which feeds into the compatible PDA, Smartphone, laptop or PC.
Buy Virtual Laser Keyboard at $199.99USD
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If you’re still feel not fast enough for input data into your PDA even using the “Auto complete input - Quick Write 5″, then this