QuickCal for iCal!
QuickCal is a new widget to add events to iCal from the dashboard. It is also possible to add to-dos. It is not obvious how to use the widget at first, but as soon as you start typing in the box, it suddenly makes sense. You are also sure that it is doing what you want, because it displays what it is going to do just under the text box as you are typing. You can download the widget here from MacUpdate.