ADVANCE PREPARATION: Soak the bamboo skewers in water for 6 hours.
Cut the salmon into 12 rectangular pieces, each about 3 inches long, 1 inch wide, 1/4 inch thick.
Place 1 piece of salmon on a cutting board.
Put the fingers of one hand on the salmon to stabilize it; with the other hand, push the skewer down the length of the salmon piece.
The skewer should be visible only at either end.
Repeat with remaining pieces.
Combine the sesame oil, sherry, soy sauce, olive oil, pepper, cilantro, and ginger.
Rub the sauce over the salmon and marinate for 1 to 4 hours.
Prepare optional dipping sauces.
LAST-MINUTE COOKING: If broiling, place the broiling rack at the highest setting, then preheat the broiler to 550 F.
Line a baking sheet with foil, set a wire rack on top, and coat the rack with nonstick spray.
Lay the salmon pieces on the rack and cover the exposed ends of the skewers with pieces of foil.
Turn the oven setting to broil, and broil until the salmon loses its raw outside color, about 2 minutes.
The skewers do not need to be turned while broiling. (If using an electric oven, leave the oven door slightly ajar during cooking. ) If using a gas barbecue, preheat to medium (350 F).
If using charcoal or wood, prepare a fire.
When the coals or wood are ash covered, brush the barbecue rack with cooking oil, then grill the salmon about 1 minute on each side.
Brush with the reserved marinade during cooking.
Serve at once, accompanied with one or more dipping sauces.
Each person spoons a little of the sauce down the length of the salmon, and then nibbles the fish from around the skewer.