"Please feed me. Now burp me." - Polly Dolly
Means by which information and contraband may be transmitted covertly.
The first known occurrence of KAOS's use of dolls is the case of agents led by the infamous Herr Bunny operating out of Bowers Department Store who substitute recorded voice cartridges in Polly Dolly dolls with cartridges containing stolen information on Project Skyblast and then send the dolls out of the country [Episode #4: "Our Man in Toyland"].
Four years later, Miss Valerie's team reverses the process and uses talking dolls to smuggle a formula for a deadly explosive into the country. A number of dolls are also rigged as explosive devices in their own right [Episode #115: "Valerie of the Dolls"].
CONTROL has also used this method on at least one occasion, with the Chief issuing instructions to Max and 99 via a doll planted at Bunny Beebe's Bye-Bye Baby Buggy Bargain Bazaar on Barnaby Boulevard [Episode #114: "Ironhand"].