Heat grill. Rinse salmon and pat dry with paper towel. Place in a self-sealing plastic bag with tamari sauce and ginger. Marinate 15 minutes, turning once. Cut baguettes in half lengthwise and then cut each piece in half crosswise. Spray cut sides with olive oil spray. Set aside. Mix wasabi powder and water together to form a paste. Mix paste into mayonnaise. Set aside. Remove salmon from marinade and pat dry with paper towel. Spray grill grates with olive oil spray. Place salmon on grill about 5 inches from heat and grill 2 minutes per side. Salt and pepper cooked side. While salmon grills, toast the bread on the grill, cut side down, for 1 minute. (The timing will be the same using a range-top grill.) If broiling, line a baking tray with foil and spray with olive oil spray. Broil about 5 inches from heat for 2 minutes per side and toast the bread for 1 minute, cut side up. To serve, spread each slice of bread with a layer of the mayonnaise mixture. Place a salmon fillet on 2 of the slices. Place scallion slivers and cucumber slices on the salmon. Cover with the remaining bread slices. Per serving: 564 calories, 42 g protein, 42 g carbohydrates, 22.5 g fat, 110 mg cholesterol, 1,038 mg sodium. Calories from fat: 34 percent. ...