Some keep deleting questions with a lot of discussion, both relevant and/or historical, and we can't search on deleted questions. Some of them are locked so that they cannot be undeleted, so I'm putting this question out, for links to be posted, so that those 10ks who want to find them in the future can. I think topical will be the best way to organize it.
What is a Community without History?
See also https://meta.stackexchange.com/questions/73455/popular-deleted-questions-list for deleted questions on other sites (for 10k users)