My wife does this every now and then and it is always fun to participate. She calls it "blast from the past." What you do is blog about your past, include a picture and a little story about the picture.
Next spring, as we were getting ready to go to church, I looked down below the window and saw this strange plant. Isn't that a tomato plant, I asked my wife. How did that get there? Finally I realized it was from the tomato that someone had thrown against our window. That plant grew as tall as half way to the top of the window in the picture, (in the picture it is still a small plant), and gave us huge delicious tomatoes that year. It was a perfect example of how God turned something meant for harm into something good.
Last year, a stolen vehicle plowed through our yard, hit our car, and smashed our car against our house, directly below that same window. As I went outside in the dark to survey the damage to our car below that same window, the Lord reminded of how he turns bad things into good.