Good find.
llustrator and Photoshop can do those similar things with brush affects if you build an affect how you want and save it as a custom brush affect preset for example, I have made christs bulbs with glint highlights in them, and used random spot colors. Draw a random string of bulbs and light on the trees and click on the brush. Christmas tree lights and bulbs everywhere. You can set them to flow randomly as well. Try snowflakes or stars in a sky.