Slack isn’t just another office collaboration app. The company has been called, “the fastest-growing workplace software ever.” Recent press reports claim that “users send more than 25 million messages each week,” and that the company is, “adding $1 million to its annual billing projections every six weeks.”

Smelling an opportunity, investors just plowed $120 million into the company, giving it a $1.12 billion valuation.

“Our subscription revenue is growing about 8