I regularly use remote access with SSH, VNC, and RDP. Ubuntu comes with Remote Desktop Viewer (vinagre) for VNC/SSH, and Terminal Server Client (tsclient) for RDP. Remmina is a remote desktop client that does a better job supporting all three protocols.
The main window is a simple list of your remote hosts, which can be grouped into a tree.
New RDP, SFTP, SSH, VNC, and VNC server connections can all be configured using a graphical dialog, complete with advanced options and SSH tunnel support.
Besides having my RDP and VNC/SSH connections saved in the same place, my other favourite feature is the Grab all keyboard events button. When I was using rdesktop to RDP to Windows systems, I couldn’t switch workspaces on Ubuntu because the remote system would grab the key combination. In Remmina, unless I select Grab all keyboard events, workspace switching works fine.
Install Remmina by finding it in the Ubuntu Software Center, or by installing the package remmina:
sudo apt-get install remmina