The original, iconic and much replicated Robby the Robot suit is up for auction.
Via Bonhams:
In 1970, Robby and his Jeep were purchased privately from M-G-M by Jim Brucker and both were displayed throughout the 1970s at Movie World/Cars of the Stars. By 1979, Robby had fallen somewhat into disrepair; filmmaker and collector Bill Malone, who had previously built the first full Robby replica, acquired him that year. Using original spare parts included with Robby, Malone restored him to his full glory. (Robby's current hands are recasts from his original hands; the originals were rubber and naturally deteriorated over time. The "bubble" dome on Robby's head is not an original but was made from an original M-G-M studio mold. An original Robby dome is included which has yellowed with age.)
After Robby's restoration, he occasionally cameoed in films like Gremlins (1984) and periodically made public appearances at conventions, screenings, and other events, including the 2016 Turner Classic Movies Film Festival. He has been replicated countless times as toys, model kits, and other memorabilia. Robby was also recently honored by the Academy of Motion Picture Arts and Sciences in a special retrospective of Forbidden Planet; he remained on display at the Academy for two months. The original Robby is fully operational, has been carefully maintained for nearly four decades, and is as stunning as ever.
I prefer B9.