When you want to create a task based on the contents of an email message, you don’t have to re-enter all the information. Instead, click the message and drag it to Tasks on the navigation bar.

The contents of the message, except attachments, are copied to the body of a new task. A task created this way is the same as if you create a task from scratch, except you save time as contents from the message are automatically added to the new task. Just like for any task, you can set a due date, add a reminder, or assign the task. Also attachments are included.