Check this link out : http://filemakerinspirations.com/2010/10/dynamic-portal-filtering-while-you-type/
You create a serach field then as you type, it filters the portal base on what you are typing in the seach field. The seach field can be setup to search any field in the portal. You just have to add to the filter.
Hi S Chamblee. Thanks very much for your response. I actually use that very solution for a search field that searches the same portal (I'm pretty sure you recommended it to me in an earlier post!) I was trying to add this "Rolodex" type function in addition to the search field. Wouldn't be the end of the world if I couldn't make it work, but was hoping someone had already accomplished this.