StickyNote is a very good option that will help you remember events on your computer desktop. With this application you can create simple text notes or notes with 3D effect of different colors and stick them to your desktop.
You can move your notes to the preferred position, stick them to an open window, and send them via email. You can also hide them to avoid using too much space on your desktop. You can use your regular e-mail to send notes to other people; you just need to configure your e-mail account. Also you can receive notes from other people directly to your computer desktop.
Notes can be arranged by categories, besides, they can be used as reminders with sound alarms. You can attach files or web kinks to the notes as well. Another advantage is that you don't need to change your calendar, StickyNote gives you the option to synchronize your notes, appointments, and address book with your Palm or Microsoft Outlook. You can also password protect your notes to prevent them from being seen by others. If you like to use hotkeys, you can also configure them for different actions.