BenkoDesk lets you use Trello for shared/team emails. Connect up a Gmail account to a Trello account and you and your team can easily send and receive emails directly from Trello cards. Replaces things like HelpScout for 1/10 the cost!
Just like Google Docs, Spreadsheets & Slides, with Mailie emails are now sharable. Use this Chrome Extension to create sharable links to any thread in Gmail - for announcements, documentation, discussions.