Before starting to spend real money on creating end-products you need to figure how the end-product will be by creating basic, small-scale and inexpensive mock-ups. In moderns days building a prototype involves many people especially from the design team.
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Electric car claims 0-to-60 mph in 3.2 seconds
Windows 7 Asus Phone spotted in Pakistan
Video: Acura NSX hybrid prototype in action
Foxconn showcases smartwatch prototype (for the iPhone)
Early iPhone prototype: 5×7-inch display and serial port!?
Valve's Steambox prototype may be imminent
Video: Polytron builds a transparent smartphone
Ice Computer touts modular XPC
Samsung showcases flexible OLED smartphone prototype
This Android smartphone prototype has an E Ink display
RIM woos developers with BlackBerry prototype giveaway
Video: Navy railgun in action
Finders of iPhone prototype sentenced