Amazon was granted three new patents which cover purchase circles, search results in the form of products from multiple product categories and even consumer reviews:
Patent 6,963,848 filed March 2, 2000 and granted November 8, covers "Methods and system of obtaining consumer reviews".
Patent 6,963,867, filed on March 31, 2003, covers "Search query processing to provide category-ranked presentation of search results".
Patent 6,963,850, filed on August 19, 1999 covers "Computer services for assisting users in locating and evaluating items in an electronic catalog based on actions performed by members of specific user communities".
More info over here. What a bunch of crap. Can't the patent system be altered to prevent people from getting a patent on way too obvious things like these?