MyChat is an enterprise messenger with own server that can work in LAN or over the slow Internet connection.

Tight is a Chrome extension that increases readability, removes many redundant/useless buttons, improves the page layout and modernizes the overall style of Slack. It's open source — suggestions and pull requests are highly encouraged!

Snap Scroll is a Chrome extension that lets you use a long click (for one handed use) or Alt+click (faster) anywhere on the page to instantly scroll to that point. Having paragraphs and posts snap neatly to the top as you hop through them reduces distraction and is surprisingly satisfying.