Not necessarily a Publisher feature... Fireworks and Gimp have it (even as in Gimp is a PITA to implement it)...
Fireworks ---> http://help.adobe.com/en_US/fireworks/cs/using/WS3f28b00cc50711d93f3703bc133a3ec962f-8000.html
It would be tremendously helpful if Designer (and Photo!!!) would have this feature as well...
I was doing some timetables for a band that is currently touring, for their fan board - X plays in this city at 7.00 PM... so it's at this hour in NY, this hour in Buenos Aires, this one in Tokyo and so and so). I have a template for this, but a find/replace text feature would definitely save a lot of time and effort for the task...
this is one of those minimal things for I still can't get rid of Fireworks/GIMP for good =(
hopefully the developers consider it...