I recently came across a spreadsheet where a cell was double clicked for the
multiple options to become available.

This was similar to a drop-down list, but there was no drop down list!!
Confused?

An example...

The cell currently shows a value of "A".
I double-click on this cell ... the cell changes to "B".
The new value is not random, but coming from a pick list or a pre-determined
list.

Does anybody know how such a feature is created?

Regards,

andym