Connect remotely to VM (RDP)

Enable RDP (Remote Desktop Protocol) for the vm you want to connect to:

$ sudo VBoxManage modifyvm vmName --vrde on

Connect to running vm:

$ rdesktop -a 16 192.168.0.100

References
http://www.howtoforge.com/vboxheadless-running-virtual-machines-with-virtualbox-4.0-on-a-headless-opensuse-11.3-server-p2