Microsoft Teams, the new chat-based workspace in Office 365
When Office 365 came out, I mostly compared the price to Google Apps and didn't really think Office 365 brought that much value.Now, you can have a Google Apps, Slack, Trello, and Evernote alternative for your business under one subscription.  Even if you choose the plan for installed Office applications on your computer, the price is still much more attractive than having to get a subscription for every one of the competitors.Edit: They even have a Zapier and IFTTT competitor:https://flow.microsoft.com/en-us/