Have had multiple experiences of quick karma.
One day I went to the store where M bought his favorite sausages. I took a picture on my cell to send to him. It wasn't my intent (or at least 100%) to be mean, rather a taste of home, per se. Well, karma didn't think so. So in the store the container of watermelon I was carrying spilled onto my shirt. Something else happened before getting into the car. And when I parked my car in the parking spot I can now use because M is gone, I scraped the side against the wall.
Then more recently one morning I was joking with one of the guys at work. He held the door open for me, and I then walked really really slowly. And then, that very afternoon, I held the door for another guy, and he walked really really slowly.