How to Filter Posts Using Custom Fields on Wordpress Like Amazon, etc
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Does anyone know of a plugin or easy method to be able to filter (not sort) posts based on multiple custom fields? I am looking to do something like the left filtering bar on Amazon: http://www.amazon.com/s/ref=nb_sb_noss_2?url=search-alias%3Dstripbooks&field-keywords=computer

Users would be able to select a star rating, select star amenities, etc, and the query_posts loop would return only posts that had relevant values for all of the filters the user sets.

Plugin would be fine but if its a small enough block of code, would love to learn how to write it instead :)

Thanks for any and all help!
-Ryan