Graph Your Inbox is a Google Chrome extension that allows you to plot on a graph any activity on your Gmail account over time. Activities include email conversation with a particular contact, mails containing a keyword or phrase, mails with particular labels etc. By allowing you to visualize your communication, you can uncover all kinds of statistics about your Gmail usage.
Just launch the extension and enter any keyword to search. For example, you can search for ‘Twitter’ to find out how many Twitter followers you gained over time. Another possibility is to find how often and when you correspond to with your friends. Results are displayed in graphs and charts. Individual data points on the graphs can be further explored to reveal subject headings, which can be clicked to open the associated email messages.
Advanced Google search operators like “label”, “to” and “from”, and other metadata that Google typically accepts can be used in Graph Your Inbox. Several queries can be merged and compared with different colored graphs. How was your email relationship with Bob during the last year as compared to Steve? And things like that.