If you have the money Profiles in History is auctioning props and collectibles related to Transformers and Transformers: Revenge of the Fallen. Items for sale include the Hero Bumblebee robot (not sure if same as one used at the various premieres), the 1977 Camaro (Bumblebee) used in the first film, Jetfire's cane/landing gear, various NEST gear and weapons, Tomb of the Twelve pieces, stunt Matrix prop, actor costumes, Hero Wheelie RC truck, and more. The only caveat is the value of many of the props is measured in thousands of dollars. Even if you don't have the money, the images of the various props are interesting. Each piece includes an image, description and size and comes with a certificate of authenticity from Bay Films and Paramount Pictures.
Two ways to view the available pieces. Either click here, or go to the Profiles in History and type "Transformers" in the search field. Thanks to Scorpio for the link (via the Allspark).