i really can't understand, why devs use Slack, HipChat or other Cloud Chats for internal communication.
Its even worse that three of my team use Hipchat in a Channel which the Mod is a former employee!

I find it very good! It's useful for searching for information in conversations. How many times have you thought "X said something but can't quite remember what it was"? It also has a decent calendar for reminders and being able to pin attachments is also handy. It's good for distributed teams as well with screen sharing and video calls.

@dan-pud You can also get that stuff with non-proprietary software (like RocketChat) on a server that you own.