Combine sake, soy sauce, sugar, ginger slices and lemongrass in heavy small saucepan.
Bring to simmer, stirring to dissolve sugar. Simmer teriyaki glaze 10 minutes to blend flavors. (Can be prepared 1 day ahead. Cover and store at room temperature.) Strain.
Preheat broiler.
Arrange salmon skin side down on broiler pan.
Brush salmon generously with teriyaki glaze.
Broil without turning until cooked through, about 8 minutes, brushing with glaze every 2 minutes.
Place on plates with steamed bok choy and baby corn, and brown or white rice. Place remaining glaze in ramekin or sauce cup and serve.