Great article from Business Insider that details some of the different failed bits and pieces that Microsoft came up with over the years. The cool part is that they connect the dots and show how they may have led to superior versions of the Windows technology that we see today.
Some of the examples that were cool are:
Pocket PC 2000 eventually became the ill-fated Windows Mobile.
Released in 2000, this was meant to let Microsoft’s hardware partners compete with the Palm Pilot. Like Windows for Pen Computing, it required a stylus.
It later evolved into Windows Mobile, Microsoft’s first portable phone OS. Windows Mobile sold pretty well for a few years, but the iPhone and Android leapfrogged it and Microsoft had to start over with Windows Phone.
Windows XP tablets came out way back in 2002, but never sold well.
This special version of Windows XP was released in 2002, and Bill Gates talked it up and was a big internal supporter. Maybe it was ahead of its time, or maybe the stylus turned a lot of users off. Whatever the reason, the first crop of Windows tablets sold slowly, and eventually Microsoft built this functionality into Windows Vista and stopped promoting it as a separate product.
It has a lot of interesting examples of Microsoft technology that quite frankly I forgot about..
It puts the technology levels of Windows 7 and Windows 8 in perspective.