Dependent drop down lists is an AddIn for Excel 2007/2010 (not Mac!) that let´s you easily create drop down lists (comboboxes, form controls) in Microsoft® Excel. A dependent drop down list changes it´s values automatically depending on selected values in previous drop down lists on the same row.

Features
Utilizes a pivot table to quickly filter and sort values for maximum speed
The drop down lists are populated using Visual Basic for Applications
No excel formulas
Easily copy values: Each drop down list is linked to the cell behind.
You can create as many drop down lists you want
You can send workbooks containing dependent drop down lists to friends, colleagues etc, as long as they can open macro-enabled workbooks.