A subset of tech community in Japan has established a strange form of "broadcast" yourself in Slack, which is called "minute-updates" channels, that is, each team member creates a channel owned by oneself, posts short updates (or tweets, if you like to think in that way) there, and lets others chime-in freely. So it's a channel for monologues out loud. This clearly doesn't scale for large orgs, but any communication…
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