Another tip: open vnc://[user@]host[:port] connects as user to host on port with Screen Sharing, and, more generally, "open URL" works for any URL scheme

Another tip: open vnc://[user@]host[:port] connects as user to host on port with Screen Sharing, and, more generally, "open URL" works for any URL scheme registered with Launch Services, including, but not limited to, the obvious ones.