I think for a lot of us hip young people you Skype, Slack, Google Hangouts, etc. - but I’ve recently received a few requests for more traditional teleconferencing at my space. I seached past threads for suggestions but some of the projects seem to be discountinued like Fedora Talk. But I came across a really interesting project called Riot.im: https://about.riot.im/ that lets you have unlimited call participants, and you can set it up on your own server to ensure it’s not affected by Skype being overloaded or down.
Riot.im is my top choice, but there’s also Asterisk, which is more of a traditional solution - which lets you dial people in through conventional phone numbers, but it is also integrated with things like Google Hangouts. You can also buy hardware from them for your teleconferencing room, which makes it seem a bit more professional. Here’s more info about Asterisk: http://www.asterisk.org/
Are you using any teleconferencing solutions that you’d recommend? Let me know!