An MSU that will allow you to upgrade a copy of Windows 8.1 to the leaked version of the update 1 that will arrive this spring has been leaked and is now available for download.
NewerTech Wireless Aluminum Keypad Review
NewerTech Wireless Aluminum Keypad
Office 2016 launching this year, touch apps coming soon
Microsoft reveals the next version of Windows 10
Introducing Windows 10 for phones
Hands on with HoloLens
Download: Windows 10 build 9926