Cook the rice according to the package directions.
Meanwhile, in a medium bowl, combine the mangoes, cucumbers, ginger, lime juice, 1 tablespoon of the oil, the cilantro, 1/2 teaspoon salt, and 1/8 teaspoon pepper; set aside.
Rinse the scallops and pat them dry with paper towels. Season with 1/4 teaspoon salt and 1/8 teaspoon pepper. Heat the remaining oil in a large skillet over medium-high heat. Add the scallops and cook until golden brown and the same color throughout, about 2 minutes per side. Divide among individual plates and serve atop the rice with the salsa.
Tip: Look for scallops that are translucent rather than stark white; they'll taste fresher. Some arrive in the store with the muscle still attached. A quick tug with your fingers before cooking will remove the muscle easily.