A few years ago, there was an exhibition at the powerhouse museum in Sydney about the history of computing. A friend and I managed a really convincing imitation of nostalgia looking at computers from the early 80s. I think a major nostalgia trigger is seeing (or hearing, or smelling???) something you haven't for a long time, and that can easily apply to individual models. I wouldn't be surprised if it manifests for operating systems or "look-n-feel"s, they change regularly enough. Oh, and mobile phones.