Clearly Slack has out-innovated here...
I just don't know what we would ever do if these genii hadn't invented threaded messaging.
</sarcasm>
I don't hate anything about email except spam and the measures necessary to contain said tsunami.
What is super amazing is how well this intra-machine user-messaging system scaled OUT of said box in the first place. (it was only ever supposed to be for users of one mainframe computer to message each other...)
"inter-network email" = wow. who knew it would even work.