| I use IRC, but come on. It offers a lot more than IRC right out of the box. * File uploads * Embedding portions of links (tweets, images) * A very good search * Multi-line posts * Code-formatting, including multi-line posts, and also snippets. * A mobile client that alerts you when someone mentions you. * Scroll-back history when you sign on at any time. * Syncing between multiple clients. Yes, you could create a bot or modify an irc server to do this, and then find or write a client that will do all that stuff, and an irc bouncer can fill in for a lot of this. But Slack does it out of the box. Zero extra work needed. I like IRC, but if you claim that Slack doesn't offer anything more than IRC, you're either delusional or using an incredibly broad definition of IRC. |