The idea: - Run Windows in Virtualbox - For the host, use a very minimal Linux/X11 system - Allocate most RAM for the VM, leave a bit for the host - Use Virtualbox snapshots for instant rollback This way the snapshot/rollback mechanism runs mostly outside of Windows. The problems: - Performance. Driver support on a Linux virtualbox host will not be as good as native. - Security. I frankly do not trust the Virtualbox guest extensions. - More security. Virtualbox is hard to confine effectively via access control. - Even more security. Virtualbox does not run at all under GrSec kernels. - Memory management. With Xen you can allocate a small contiguous chunk for the host, and leave the rest for guests. AFAIK this cannot be done with Virtualbox, which might be an issue when allocating over half the RAM for the guest. Any thoughts on this? I actually tried to set something like this up last weekend (using Debian 8 as the base), which is how I discovered that GrSec and VBox don't get along. Needless to say I did not get very far.