Zenity - Zenity is a tool that allows you to display GTK dialog boxes in commandline and shell scripts.
Zoom - Equip your team with tools designed to collaborate, connect, and engage with teammates and customers, no matter where you’re located, all in one platform.
Yad - Yad (yet another dialog) is a fork of Zenity with many improvements, such as custom buttons...
WebEx - Cisco WebEx Web Conferencing, Online Meetings, Desktop Sharing, Video Conferencing
Glade - Glade is a RAD tool to enable quick & easy development of user interfaces for the GTK+ toolkit...
GoToMeeting - GoToMeeting is a web conferencing service offering a range of services which are available on Mac, PC, iOS and Android devices.