Professor Milo, Batman: The Animated Series

Dead products at Microsoft are a couple a month, on average. Microsoft has been cutting down expenses by ending many products and closing down divisions for a few years now, leaving the profitable ones in tact and giving more time to losing products, hoping for some reversal or cross-product leverage (e.g. Zune being used as a tool/means to lift Xbox). The latest dead product from Microsoft is poor Milo, which is said to be canceled although Microsoft cannot confirm this just yet. To quote one report among many:

Kotaku's reporting that the plug's been pulled on Lionhead Studios' ambitious Project Milo for Kinect. The undertaking–also referred to as Milo & Kate–was the jewel of Microsoft's 2009 E3 presentation, containing the most forward-looking of the motion-gaming ideas during the press conference.