1. To make the meatballs: Combine all ingredients well. Mixture will be sticky. Using damp hands, divide into balls and set aside.
2. In a high-bottomed saute pan, combine orzo, broth and sea salt. Mix well. Place meatballs on top of orzo. Bring to a rolling simmer. Cover and reduce to a simmer. Cook for 15 minutes, until most liquid is absorbed and meatballs are cooked through.
3. Stir spinach into orzo. Cover and cook another 2 minutes to wilt. Top with feta and serve.