In a large mixing bowl, mix together the cream cheese, sour cream, soy sauce, ginger, garlic, sugar and MSG until smooth and well-combined.
Thoroughly fold in the crab meat and green onions to the cheese mix.
To form the crab rangoon: Place the small bowl of water on your work surface.
Place a wonton wrapper on your work surface. Place 1 to 2 teaspoons of the cheese and crab mix in the center of the wonton wrapper (the proper amount depends on the size you bought).
Take your finger and dip it in to the water. Run your finger on the outside edge of the wonton square. Then gently fold it over to form a triangle shape. Seal the edges firmly so they don't open during frying. You will find that as you seal one edge, the other may raise a bit, that's okay, go with this, it makes the process quicker and easier. Once you get the hang of it you'll be moving right along. Grab another person to help and you'll be flying!
Place each finished crab rangoon on a large sheet of wax or parchment paper. Cover with a kitchen towel to keep moist while you make the others.
When finished forming the crab rangoon: Place a pan suitable for deep frying over medium-high heat. Immediately pour the peanut oil to a depth of about 2". Heat to 350°F.
Cook the crab rangoon in the hot oil (turning once) in small batches. They cook quickly. When finished frying, remove them with a spider or slotted spoon and drain on a rack or paper towels.
Make extras to freeze and enjoy later.