A linux distro that instead of setting up dual boot, will automatically make a virtual copy of the boot partition and bring up the original OS in a virtual machine.  The preferred configuration would be with a dedicated second display (since they are so cheap and universally available), but if only one display is available, it could create a generic virtual display a bit smaller than the host machine's display.  It would be an option whether the VM would be brought up at every boot or only upon a simple command request.  Another option would be with a second disk installed, so the original operating system's disk is left unchanged (or perhaps the partition shrunk to make room for a shared data partition, in which the original boot partition would have to be virtualized to protect the space removed from that operating system's exclusive control).
 
when I asked simple ai-search, i was told such did not exist yet, and it would be difficult to run gaming in the VM, but I don't care if gaming will run there.
 
Even cooler, with a second disk installed, would be to boot either OS (either disk) native, and automatically bring the other one up virtual...
 
"standard" process:
--shrink original primary partition to make room for linux
--make partitions as desired and install linux in the new area
--create disk image of boot cylinders/partition table, modified to not include linux and end where it starts
--if desired, (not sure of details) duplicate  virtual images of UEFI for linux or the original os, or make additional real partitions.  I don't think they can share them, can they?
--put linux boot into real boot cylinders
--concatenate the virtual disk of the original boot cylinders with all of the other original OS partitions into a virtual disk used for booting the original OS in a virtual machine.
 
Any naysayers saying "can't do that" or "too hard" will get my usual refrain... 
 

Carey