Are you using your email account as an archive? If you are, you might want to keep your eye on how much of the available storage you have used and occasionally get ride of things you definitely don't want anymore.

Some people like to save everything and others just don't want to deal with throwing out what they don't want. But eventually both of those practices can cause the same problems that being a packrat in the brick and mortar world causes—spaces and clutter issues. Email with large attachments can use up a lot of space and even though many of the email accounts available are increasing storage capacity for users, it's a good idea to keep a handle on what you're saving and delete what you don't want.