It’s the number of folders in the lo-fi existential alarm clock known as, a tickler file.
A tickler file is a collection of date-labeled file folder organized in a way that allows time-sensitive documents to be filed according to the future date on which each document needs action. Documents within the folders of a tickler file can be to-do lists, pending bills, unpaid invoices, travel tickets, hotel reservations, meeting information, birthday reminders, coupons, claim tickets, call-back notes, follow-up reminders, maintenance reminders, or any other papers that require future action. Each day, the folder having the current date is retrieved from the tickler file so that any documents within it may be acted on. Essentially, a tickler file provides a way to send a reminder to oneself in the future—”tickling” one’s memory.
I love the drop-dead simplicity of the tickler file concept, and that’s why I was inspired to use that name for my site.