CPU-Collector.com  
   Features a searchable collection, from early vintage to more modern models, with photos, information, specs, and forum. Includes many non Intel CPUs (ex Motorola).
   http://www.cpu-collector.com/

CPU-World.com  
   Large CPU collection organized by manufacturer and class. This site features a variety of identification tools and forum.
   http://www.cpu-world.com

CPU-Museum.de  
   German collection of early to late model cpus with photos and specs. It also features an interactive forum.
   http://www.cpu-museum.de

X86-Secret : ES Zone  
   An Engineering Sample (ES) only CPU collector web site. This site features an extensive collection of engineering samples and prototypes (mainly x86 architecture).
   http://www.engineering-sample.com

CPUShack.net  
   A rather large collection of CPUs and other support chips. The site features a photo directory organized by manufacturer.
   http://www.cpushack.net