I've tried three or four times, from my car. It was more difficult than I imagined, because of needing the "right" subject and distance, and choosing how much or what to keep in focus. Going all the way out of focus sounds ideal for next time!
Here is a quick edit from a small file (the raw file went into the trash - I vow to stop doing that!). This spring on a rainy day I parked in front of forsythia bush that was just beginning to bloom. Rain was fairly strong, so it took only a few moments to cover my windshield. I've bumped colors quite a bit, but this is still a very tame version compared to what I posted to another forum 😁