I hate email. I have to live with the tool for external communication (sales, promotion, etc.) but I have done everything in my power to remove email as a tool for any internal/project communication. Here’s why:

When you think about it, all our work is broken into projects. When we communicate with others, we are collaborating about a specific project. We might not use the word “project,” but according to David Allen, Getting Things Done guru, “...a project is anything we want to do that requires more than one action step.” Yet, when we send emails, we are using a tool that was modeled after the snail mail letter. A project has a lot more to it than sending letters to each other. It requires real collaboration. A long email chain is a form of collaboration but its not ideal and it's really hard to mine it for all the content about a single project because people just keep sending more and more letters to each other. 

Once a project starts, I highly prefer to move all the people involved out of email and into other tools that were built to encourage open, transparent, communication that can be accessed by all (especially people who join later), searched, and archived. Another advantage to real collaboration tools is that you can remove people’s access when they leave—when you do all your collaboration via email, you basically let the content go with each particpant’s inbox.