How to Share a Virtual Machine (VM) with VirtualBox Between Two Mac OS X Users

Unfortunately, VirtualBox seems to want each user to have their own VM setup. This is not an ideal situation. My wife I wanted to share a VM of Windows XP. Not at the same time, but at different times. That way it would take up less space, and I would only have to maintain one machine. From what I could tell, VirtualBox assigns a unique ID number to a VM and disk from the GUI front-end. That number is different when each user sets up the VM from their account. This causes errors in VirtualBox. I could find no way of importing an existing VM from another account, so here is what I figured out. If you want to share a VM, first delete the /Users/Library/VirtualBox for one of the users, then using Terminal, symlink the folder to the other user using the "ln -s" command. This worked quite well. Other than that little caveat, I have been quite happy with VirtualBox. Best of all, it is free.