I have to admit that one of my favourite features of Windows 7 is the ability to install and run it from a VHD file (Virtual Hard Disk file). Having the entire operating system in one file is just very handy.
The install process is pretty simple and once you have a VHD with Windows on it you don’t need to do it again. For instance you can simply copy the file somewhere else and then update the bootloader using EasyBCD to add a new entry for the new VHD file and you’ve now got a second install of Windows. Keep a backup of the file and any time you need to revert to a clean install, just copy the backup over the original.
I did this yesterday on my home computer. I installed one normal install of Windows which I’ll use for gaming (as there may be a ‘tiny’ overhead associated with running Windows from a virtual drive and I want it as fast as possible for gaming). Then I copied a previously prepared VHD to a new partition, edited the bootloader using EasyBCD and I then had a dual boot machine. Rinse and repeat for a triple boot machine (just don’t ask me why I need three copies of Windows – it makes sense in my head).
I have a similar setup at work but as I have Windows XP as the base install, I installed the bootloader on a USB drive (using EasyBCD) and added an entry for a Windows 7 VHD file. Now if I want to use Windows 7 I just boot from the USB drive and that boots into the VHD file.
Yeah I know, it sounds nerdy and dull but I do find it very useful.