Personal rules:   1) Are they someone who will attract any interesting discussion? Cliff Richard probably isn't going to drop dead any time soon, but there's always lots of rumour and innuendo about him 2) Are they actually famous? Threads for the second bass player from The Bluetones probably aren't valuable 3) Are they in the public eye? Threads about hermits won't work, which is why I wouldn't start a, say, Bobbie Gentry thread. However, Jenny Ditski got a thread from me because she was very vocal on Twitter during her final months. 4) Are you post-whoring? Please don't.