3. The method of claim 1 , wherein associating the first annotation with the calendar event comprises associating the first annotation with the calendar event before the calendar event is sent to the plurality of calendar event recipients.
1. A method comprising: with a computer, generating a calendar event that is electronically addressed to a plurality of calendar event recipients via a computer network, said calendar event being an event scheduled to occur at a future time for a plurality of participants and recorded in an electronic calendar in a calendaring application executing on said computer, said calendar event recipients receiving an electronic notification of said calendar event via said computer network; with said computer, generating a designation of a subset of the plurality of calendar event recipients as first annotation recipients, such that, with respect to the calendar event, there are both general event recipients and first annotation recipients; and with said computer, associating a first annotation with the calendar event, the first annotation comprising information additional to the calendar event as originally created, the first annotation being addressed to the first annotation recipients such that, with respect to the calendar event, all recipients are sent the electronic notification, but the first annotation is sent only to the designated subset of recipients for that calendar event.