I like running VirtualBox headless on my Mac. It doesn’t show up in the Dock, and feels like it’s a remote server.

First, figure out which VMs you have on your machine.

haddad-work:~ jhaddad$ VBoxManage list vms
Oracle VM VirtualBox Command Line Management Interface Version 3.2.6
(C) 2005-2010 Oracle Corporation
All rights reserved.

"WebServer" {2c61a180-e098-4926-b09a-27e431791c88}

Then start it using VBoxHeadless

nohup VBoxHeadless -s WebServer -vrdp on  &

I’m using Cord for RDP.

Open up Cord. If you’re using the default settings, you can just go to quick connect and type “localhost”. You’ll see your VM booting.