Link - python-vnc-viewer, a VNC viewer written python
Haven't tried it yet, but I am thinking if it might be of use together with some authentication and authorization layers...
Simple VNC viewer that is built with Twisted-Python and pygame. Originally written by Chris Liechti. The viewer supports the following encodings: Hextile, CoRRE, RRE, RAW, CopyRect The display is done using pygame because of it's good graphics performance but any GUI system can be used as the code is modular and can easily adapted. Clipboard transfer is supported but not used in the sample application.