Slack has seriously changed the way we work at my company and it&#x27;s boosted our productivity by 100x.<p>Yes we had a IRC server for a while and no one was using it, so we always had to use emails for important communications.<p>You just got to try it to feel it. Some features on paper don&#x27;t match with the experience of a product.<p>If you&#x27;re worried about using it for large community projects (e.g OSS), then maybe IRC is still the better child for that particular audience, although there&#x27;s already a couple of communities who have successfully moved to Slack entirely (Gopher comes to mind).