The fringing foot is an attachment onto a sewing machine. You can use it to create multiple different affects. In my example i have made hoops to add texture to my fabric.
The fringing foot works by using a zig zag stitch or something similar on your machine. The needle jumps over a little metal piece which then creates a hoop.
I have attached a file which shows a video of how I am using it and my final outcome.
Chiodi's Textiles Blog 