Came out of the gym just now to find that my bike had moved.....

On closer inspection, I found that it had been knocked over and then stood back up again.
Initial damage report: Smashed L/H mirror housing, mirror, indicator bulb socket, scuffed tip-over wing, scuffed pannier, scuffed bar end. I may find more later.
At least the guy had the decency to leave his number, just spoke to him and he seems decent - he's gonna get his insurance details to me tomorrow. It seems someone else stood the bike up while the guy that hit it was looking for me in the shops.
Let's see how this plays out. Can't say I'm happy about it, but accidents happen and if it gets sorted out then all will be well again.