>
>But if you know how to make a multi-select listbox, is it important to use a grid to "simulate" it? You may have a very good reason (or several), but any time I hear "How can I use xxx to simulate yyy," my first thought is "Why not just use yyy?"
>

Got 50000 parts in a grid/browse with a hot key lookup (jKey or VFP incremental search equivalent). I create a cursor called 'Tagged' with no records, PartNo and Tagged fields. Set relation from grid to Tagged. When user hits space bar I insert/delete a record into the Tagged cursor. Simple. *Great* performance.
Try that in a list :-)