In gmail, I have about 25 e-mail "labels" (like folders but e-mails can get more than one label, where as in Outlook, you can only put an e-mail in one folder). These labels range from "Moeko's Wedding" and "Job or Career Related" to "Honeymoon Planning" and "Recipes/Craft Projects." I've had my gmail account for about four years, so I've made quite the science out of keeping it tidy and organized.
Dan was looking over my shoulder the other day and laughed at me (one of those nervous, slightly concerned laughs) for having a label called "Drama." He thought I filed away dramatic e-mails and fights in their written form in this folder.
Silly Dan, I have labels for all my college courses. If you looked closely, you would see "PR Campaigns," "Anthro" and "Comp Lit."