Microsoft has just released their March 2016 edition of their 60-day evaluation Windows developer virtual machines (VM) on Windows Dev Center.
These virtual machines come in Hyper-V, Parallels, VirtualBox, and VMWare versions and essentially create a Windows 10 development environment on a PC or Mac that can be used to test code and devices or help convert existing projects to a Windows 10 supported format.
This version of the install contains Windows 10 Enterprise Evaluation Version 1511, Visual Studio 2015 Community Update 1, Windows developer SDK and tools (Build 10586), Windows IoT Core SDK and Raspberry Pi 2 (Build 10586.0.151029-1700), Windows IoT Core project templates (Version 1.0), Microsoft Azure SDK for .NET (Build 2.8.2), Windows Bridge for iOS (Build 0.1.160304), Windows UWP samples (Build 2.0.4), and Windows Bridge for iOS samples. As the name implies, these downloads are available for a 60-day period to give developers a chance to experience the full functionality of the Universal Windows Platform tools and technologies.
Microsoft began providing virtual machines for their Edge browser in August 2015 as part of a movement to encourage more develop for it.