Not sure what you mean with "share your VMs remotely".
You can of course install whatever remote server you want inside the VM but aside from that you can connect to a VM directly using VRDP.
But you can also manager your entire virtualbox instance using RemoteBox ( http://remotebox.knobgoblin.org.uk/about.cgi ) or from a web GUI using phpVirtualBox ( https://sourceforge.net/p/phpvirtualbox/wiki/Home/ ).
I'm sure there are other options as well.