The Windows Media Center wasn't exactly the most popular feature among Windows users, but many still mourned its death when Microsoft announced it wouldn't be keeping the feature around for Windows 10. Soon after that announcement, some users even found a way to get it running on the then-latest version of the OS, so it's clear that there was some love left for the software.
If you, too, miss the days of Windows Media Center, you may take some solace in knowing that its SDK has been uploaded to GitHub, as reported by The Register. The SDK was uploaded by Charlie Owen, a former Microsoft employee who left the company in 2014. The description for the project reads:
Preserving a bit of history for the diaspora that created Windows Media Center (the 'eHome' team at Microsoft) since the actual installer has gone missing from the original download link.
As for what you can do with the SDK, there's not really much to it. Windows Media Center is dead, and there's not really a lot you can do with it. You may find it interesting, though, to learn more about the ins and outs of what used to be a fairly unique part of Windows.
If you'd like to take a look at the Windows Media Center SDK, you can head over to the project page on GitHub.