Its not just hardware.
Games for Windows Live!
Games for Windows Live again
Was there a third one? Nevermind, no one cares.
Xbox Media Center (had a better run than some of them, but they got bored all the same)
I'm sure there's plenty of others, those are just the ones that spring to mind.
A lot of these things seem more like they were weak gambits to hamstring a competitor than actual products MS wanted to sell.
If a Microsoft product doesn't take off pretty quickly, they'll abandon it and leave you holding the bag. They have shown repeatedly in recent years that they don't have the patience required to fight it out in a market that has competitors. The logical response to any new Microsoft initiative is to ignore it until you can't, because its only at that point you can begin to believe that they'll continue to support it.
Microsoft seems to be oblivious to this effect they're causing. They say they want apps for their latest Windows phone whatever its called. But they keep resetting because their late to the party also ran didn't immediately steal a huge chunk of marketshare from two established mega corporation backed platforms and they're convinced they just need to start again to win. How many times do you think you can burn the people that actually want to develop for your platform before they stop trying?