The interesting things that start off your day

Last night I spent int, playing on the computer, watching TV and reading the book that a friend want to borrow next (and is bugging me about by SMS daily).
At one point I thought I heard a noise at the door but it didn't repeat and I thought nothing more of it.
Until this morning that is.
I climbed into my car to head off to work and there it was.
Such a simple thing and yet it dominated my thoughts until the hectic-ness of work overrode it.
And I wish my Digital camera was working so I could have captured it because the the rain required actions that erased it physically forever.
So what was it? I hear you cry.

Someone had carefully drawn a simple heart in the dust on my windscreen, right in the middle of my field of vision.

and now it's gone but the feeling lives on
And if whoever did it, reads this: 1) thanks, 2) call me :)