Mail - Notes and To Do Items
In the mail program you can create notes and to do items. Both are displayed under Reminders in the left side panel.
Notes are text (you can also attach files to notes) that can be used as insertions into email messages or can be sent as email messages. They can also be made into to do items.
To Dos are text (either a note or something selected in an email message) and then can be assigned a title, a due date, priority, and a calendar to appear on. This integrates the mail application with the calendar application nicely.
Notes and ToDos can be created from the File Menu or the command area of the Viewer Window.