Dual boot Android and Windows Phone 7 on your HD2 - HTC Source
Those of us that own HTC HD2’s (and those of us that follow HD2 news) should know what an incredible powerhouse of a device it is. The impressive list of operating systems and configurations (5 operating systems and 2 different boot configurations as of this writing) available has just been augmented further with the ability to dual-boot both Android and Windows Phone 7.
According to a thread over on XDA Developers, you can now run Windows Phone 7 from NAND (the internal storage space on the device), and Android from your SD card. It looks as if the 23 step process isn’t for the faint of heart, however, hard core device flashers should have no problems following the instructions. It looks like any SD-card based Android build will work and the poster claims that you can also reactivate Windows Live services.
For more details, head over to XDA, follow the instructions and/or watch the video!