I don’t know what you do in your day to day, but for me there is a lot of conferencing with others in world, and often out of world dependant on their schedules. Skype is the usual software of choice in that department, for more than one other it is perfect, well kind of perfect. Skype lets itself down in one area, the ability to screen share with more than one other person.
Often has been the case that I will be in a three or more person conference and someone wants to share something happening on their screen, or show what they are working on in Maya/Blender or whatever they are using. Or I myself may have learned a new PS trick and want to show the girls, but either have to explain it in words, or show them one at a time, and vice versa.