Setting up multiple/custom inboxes with labels/filters is a great way to effectively manage and organise your emails/tasks.
Example workflow: an email lands on your inbox - someone asks for a certain document > you don't have the doc now so label the email as "follow-up" > Archive the email - now it appears in your Follow Up inbox > Go look for or create the doc > Come back to the Follow Up inbox, reply with the doc > Change the label to "waiting" as you might want to follow up with the requestor and ask if they have any outstanding question on the document in a week's time > the email moves to the Waiting inbox > You review the Waiting inbox periodically and follow up as needed > If nothing else is to be done (the requestor is happy with the doc) > Remove the "waiting" label > Task done

