For Soy-Sauce Grilled Shrimp:
Whisk the soy, lime juice, honey, ginger, garlic and canola oil in a medium bowl until combined. Transfer half to a food processor fitted with the blade attachment and set aside. Add the shrimp to the marinade in the bowl and toss to coat. Cover and refrigerate for 15 minutes.
While the shrimp marinates, whisk together the rice vinegar, soy sauce, canola and sesame oils, scallion and cilantro in a small bowl.
Heat the grill to high. Remove the shrimp from the marinade, brush with canola oil, and season with salt and pepper. Skewer the shrimp and grill for 2 to 3 minutes per side, until just cooked through.
Toss the spinach with some of the vinaigrette and mound in the center of a serving platter. Arrange shrimp around spinach and spoon over more of the dressing. Scatter the peanuts over the salad and shrimp.
For the New-Style Scampi:
Add the butter and red pepper flakes to the marinade in the food processor, and pulse until combined. Scrape the mixture into a small saucepan and put on the grill just to melt the butter.
Trim the ends from the limes and halve. Brush with canola oil, season with salt and pepper, and grill, flesh side down, until marked and slightly softened, 4 to 5 minutes.
Skewer the remaining shrimp, brush with canola oil, and season with salt and pepper. Grill for 2 to 3 minutes per side, until just cooked through. Slide the shrimp from the skewers into a shallow bowl, pour over some butter sauce, and toss to coat. Scatter the cilantro over the top, and arrange the grilled limes around the shrimp.