Date added: April, 10th 2017 - (Open Source)
TightVNC is a free remote control software suite. Whereas scoring low at security features, as all traffic is sent unencrypted, this tool is still straightforward and easy-to-use. It only needs an assigned digit code and a password to establish a remote connection. One may use it as an interactive tool in administration, education or tech support. It is cross-platform, which means that is it can be used from one OS to another. Recently receiving some bug fixes and features, this VNC tool also works on slow internet connections. Including a Java viewer and multi monitor configuration, it additionally enlists a long number of server options.
TightVNC (64-bit) TightVNC (32-bit)

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