2 colors for one ical event Is it possible to put two colors, representing two people, for one event on iCal?

For example, if both my wife and I are included on a calendar event, I would like to see both her and my colors against the calendar event.
No, the colors are linked to the calendar, and in iCal a calendar can only have one color. All events for this calendar will be in the same color.

Alternatively, you could create a seperate calendar for shared events with a different color, and save the event there, or you can share each other's calendar so your wife's calendar appears in your calendar list with a different color.