smart boobs 

small breasts like a smart car is to a regular sized car

Guy1: Whoa that chick has small boobs!
Guy2: Yeah that chick has smart boobs

smart boobs by Lagoona January 10, 2011

Smart bombs 

Noun. Euphemism referring to a pair of female breasts, which, once activated, can be pointed at a male target and zero in on his most vulnerable area, rendering it under the control of his attacker. (Not his brain.)

knockers, hooters, boobs, tits, Smart bombs

Smart bombs by Queen of the Smart bombs September 23, 2009