One we implemented is a Random / Water Cooler slack channel. Keep it worksafe, but otherwise anything goes. Best thread we had was on at-home storage options,

One we implemented is a Random / Water Cooler slack channel. Keep it worksafe, but otherwise anything goes. Best thread we had was on at-home storage options, how to hack synology to do [X], people sharing code for said hacks, etc. Daily chats and people bringing discussion topics on the regular really helped with team cohesiveness.