My wife kept asking me if there was an ITT at the Pentagon. (Aside: ITT stands for Information Tickets and Tours - a place you'll find on most military bases to buy military-discounted tickets for local amusement parks and attractions).
Survey Says: YES!!! (Ding! Ding! Ding! Ding!)
It's not called ITT, but there is a place where you can buy discounted tickets for stuff. It's in the Air Force Morale Welfare and Recreation office in the 5E900 corridor. It's a shop similar to the Pentagon gift shop but sells exclusively Air Force paraphernalia, in addition to selling discounted tickets.
In the process of searching for this place, I discovered the Air Force has built a veritable art museum in their section of the Pentagon.
Seriously folks, if you take family or friends on a tour of the Pentagon, you should go out of your way to go see the Air Force artwork in the 5A900 and 5E900 corridors. There is a LOT of really amazing artwork there - mostly paintings of various styles and eras. Go check it out!