Last year I attended Salt Lake City Comic Con (again) and Matt Smith and Alex Kingston were there! I knew they'd been invited ahead of time and set to work on this piece with the intent of them autographing it for me.
I made a print of it for each of them and presented that to them at the time of signing. Both of them were incredibly gracious and kind. It was a really fantastic experience.
So here is the finished version before autographing and after.