Personally, I have no problem with resurrecting old threads, so long as it's made clear that you are. Oh, you'll still get people responding to those who have left long since--one way or another!--but that can happen on threads that haven't fallen completely dormant and have just gone on a really long time.
"Now everyone was giving her that kind of look UFOlogists get when they suddenly say, 'Hey, if you shade your eyes you can see it is just a flock of geese after all.'"
"You can't erase icing."
"I can't believe it doesn't work! I found it on the internet, man!"