18. What is your most terrible memory?
Since a lot of folks may not want to answer that one, I'll broaden it a bit. You can use any difficult memory that you're comfortable sharing, or talk about how you handle hard memories in general. It's also okay if you want to post your contribution on your own journal where you control the settings.
One of my quirks is that, thanks to farmemory, my really worst memories are from other lives. So for instance, I collect bedding because I can, and just in case I ever have to put up a bunch of friends turned refugees. My litany for bad days goes, "No one is currently trying to assassinate me. I am not personally responsible for saving the world in the next 24 hours. If this building/vehicle catches fire, there is an entire atmosphere of breathable air into which we can flee." This really puts a flat tire in perspective.
Because those memories influence how I handle problems, it's a useful thing to know about me. Even if you don't believe in farmemory, you can still observe the effects.
Oh, and for those of you who, like me, find "worst pain imaginable" to be ludicrously irrelevant, try using this pain scale which instead describes the impact of the pain on what you can do as well as comparing it to common benchmark causes.