This is an easy way to look almost anywhere under the map from any flat, or slightly angled surface.

Step 1:

Be in the passenger side of a vehicle the flips directly unto its back.

Step 2:

Hold LT to aim and you should be able to see under the map into the large void below.

Effect:

You are in a vehicle which is flipped, viewing the nothingness that exists under the gaming map. Using covertibles hightens the effect as you literally stand upside down into it.