About a year ago, A9 made big News by introducing some neat features like block-by-block match and personalized search history to refine search further. A9, owned by Amazon.com, is now scaling back:
 Discontinued features include a personalized search history that allowed users to check their search and click history and a mapping feature with block-by-block street-level images of major U.S. cities (http://maps.a9.com/).