Do you not have seperate channels for that sort of thing? We have a channel called "big-wins" where the sales people can flag up new/extended deals. I have it muted but check it out from time to time to see if we've bought in any interesting customers.
Channels and channel discipline are the key to keeping Slack manageable. Have lots of channels with specific purposes and people can choose what they care about and ignore the rest.
Urrgh. We don't have a general channel for exactly that reason. We have a channel for general chit-chat that is nothing to do with work but that's as close as it gets. Anything else work related goes into subject/team/project specific channels. We even have a shoutouts channel specifically for bigging up someone who has done a good job at something.
general channels are cancer in any communication system as far as I've experienced.
Channels and channel discipline are the key to keeping Slack manageable. Have lots of channels with specific purposes and people can choose what they care about and ignore the rest.