UltraVNC Products include many features, some of which are listed below:
All VNCs Start from the one piece of source (See History of VNC), and should follow the RFB protocol for their communications (some rather loosley). This common start point means that most of the vnc flavours (variants) available today "usually" talk nicely together, allowing for easy cross platform desktop sharing to occur.
UltraVNC has optional DSM Encryption that secures communications between the viewer and the server, reducing the possibility for man-in-the-middle attacks that would be able to see 100% of the remote screen.
Being able to transfer files to and from the remote computer is a very handy feature (especially when using the "Single Click" remote client module). This eliminates the need for emailing files to the client, and various other methods of file transfer.
Complete Folders can be transfered between the viewer and server, add to this the fact that these files are compressed prior to transfer, and you get maximum flexability with minimal bandwidth.
The UltraVNC Chat system is an embedded Text Chat with intuitive Graphical User Interface (GUI) allowing for easy and quick communication between local (viewer) and remote (server) computers.