Sometimes it would be useful to know what the SUM TOTAL SIZE of all the emails held in your mail account are, so you know if your mail account might go over its quota.
Situation: Currently my stepson has a problem with his broadband connection which means he is having to use someone else's laptop to view his emails (but he wants to leave them on the server until the phone line is fixed, at which point he can download them properly onto his main computer and delete them from the server). This problem means he is regularly hitting the email quota on his account, and it would be useful to know at a glance how close to that limit he is. I am helping by using Mailwasher Pro to keep an eye on his account and zap the spam every couple of days.
Showing the total of the listed emails probably only makes sense for a single account (I normally check several), but it is easy to clear the main window (by pressing C), then running F5-Check Mail for just that one email account.
I thought that this might be a simple-to-do and useful suggestion that other MWP users might find handy.