Apache Guacamole is a clientless remote desktop gateway. It supports standard protocols like VNC, RDP, and SSH. It doesn’t need any plugins or client software. All you need to access your desktops is a web browser.
Github: https://github.com/glyptodon/guacamole-client & https://github.com/glyptodon/guacamole-server
Website: http://guacamole.apache.org/