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As much as I dislike the event info window in OS X 10.5's version of iCal-I dislike it enough that it made my list of Leopard annoyances-anything I can do to make working with that window simpler is a win in my book. In that vein, today's hint will allow you to do make some basic modifications to an event without opening the event's editing window. Instead, you can use drag-and-drop.
First double-click the event you'd like to modify. But instead of clicking Edit, try using drag and drop. You can drag and drop a file from the Finder, and it will be added as an attachment to the event. Drag and drop a person (or more than one person, or even a group) from Address Book, and they'll be added as attendees. Drag in a URL, and it's added as a (clickable) URL. Drag and drop some text, and it's added as a note.
If your event has existing attendees, the newly-dragged people will be added to the list. If the event has a clickable URL, it will be replaced by the dropped URL. If you've got an existing note, however, your dropped text will "spring back" and not be accepted by the window in iCal.
Until (hopefully!) Apple fixes the mess it made of iCal's event input in OS X 10.6, little tips like this can make things a bit simpler-still far from ideal, but a bit more bearable.
Read article at Macworld.com