Thaw shrimp in a saltwater bath for 5 minutes. Remove tails after thawing and before cooking. Cut corn kernels off of the ears.
Heat a cast iron skillet over High heat. Add olive oil and corn. While watching out for popping kernels, cook corn untilled charred, or about 5 minutes.
Push the corn to the side of the skillet and the shrimp in to cook. Sear the shrimp for 3 minutes, flip and sear the other side for 2 minutes.
Pour in the light beer and give the mixture a good stir. Transfer mix to a large bowl. Combine the rest of the ingredients and mix well. Set aside the remaining lime wedged for serving.
Build your tacos adding the shrimp and corn mixture first. Add a layer of cheese, cilantro, and sprinkle on the chili powder. Lastly, give each taco a fresh squeeze of lime juice just before enjoying them.