This has to be a candidate for a gadget which might not be purchased by anyone. Nah, people will buy anything nowadays. It's a clip-on QWERTY keyboard for the iPhone, for those who absolutely cannot live with the iPhone's on-screen keyboard.
The iTwinge from Mobile Mechatronics
slips onto the lower part of an iPhone and gives you a real keyboard to use. That's the good part. The bad part is it covers what looks to be 50 - 60% of the iPhone's screen.
That means that if you want to use the device for anything besides typing an email or SMS you have to remove it. It also doesn't work in landscape mode, obviously. iTwinge will, according to Mobile Mechatronics, improve typing speed by 30 - 40% and reduce errors by 70 - 80%. That's all good, but ...
However, think about using it. You need to send an SMS. You slip on the iTwinge, type it out, send it. Then you want to browse to a site. You slip on the iTwinge, type out the URL, then have to remove it to see the full page and navigate. It hardly seems worth it.
The iTwinge is scheduled to ship on November 17th and the company is taking preorders now. Personally, aside from people who might order in order to review it, we can't see a market for this.