Microsoft. The software pioneer has ceded a lot of ground since the halcyon '90s when it was synonymous with personal computing. Over the last decade, an insurgent Google and reborn Apple have wrested the spotlight from the ubiquitous giant, establishing themselves as must-watch hotbeds of agenda-setting innovation.

But despite its current reputation for spending more time behind the curve than in front of it, the house Bill Gates built has never truly had an ideas problem. The Redmond, Washington-based company and its Research division have always attracted first-rate engineering and creative talent from around the world. Where Microsoft has run into problems is delivery and execution. The company seeds dozens of innovative products that seem to find equally innovative ways to fade from existence... often before they ever make it to market. For every Xbox Live, Bing or Windows 8, there are far too many bold ideas that amount to little more than vaporware—doomed to the silicon wasteland.

Here we present Microsoft's best that never were: the lost tech that, with a little more push or better strategy, could have been the next big thing.