Preheat oven to 400.
Cut each lime into 8 wedges.
Split and remove seeds from each pepper.
Place in order: lime wedge, shrimp, tomato, shrimp, pepper, shrimp, tomato, then lime wedge on each skewer.
Place on oiled rack on baking sheet.
Drizzle with olive oil.
Season with salt, pepper, cayenne and cumin.
Cook for 8-10 minutes, until shrimp are done.
Serve over rice and garnish with cilantro.