I don't know if this is possible or not:

I import data from a manufacturing process.
Column A - Date
Column B - Product Name

I want to have a table that displays the date (column A) when Product Name
(Column B) changes.

Data Example
11/01/08 8:00am 23LIN
11/01/08 8:30am 23LIN
11/01/08 9:00am 23LIN
11/01/08 9:30am 33LIN
11/01/08 10:00am 33LIN
11/01/08 10:30am 33LIN

What I'm looking for is the automatic calculation of a table that would say
11/01/08 8:00am 23lin
11/01/08 9:30am 33lin

I've tried everything that I can think of and haven't come up with anything
that's fully automated. Am I asking the impossible?

Thanks