Wang Dang Atomic Tango

 is a quest in Fallout: New Vegas.

Quick walkthrough

 * Beatrix is found in the Old Mormon Fort. You either need to convince her with a speech check, barter check, or you can give her a bottle of Absinthe.
 * The "smooth talker" can be either Santiago or Old Ben. To recruit Santiago, just ask. For Old Ben, you'll need good charisma, and high Speech skill. You may get both smooth talkers to agree, however only one will give you the reward. If you chose Santiago and Old Ben, Ben will show up and the Wrangler but you will receive no reward nor can you receive his services.
 * The sex-bot, Fisto, found at Cerulean Robotics, must have a programming holotape made by Ralph. Then, hack the terminal (science 50), (or lockpick the cabinet if you have a lockpick of 50 to get the pass card) to program Fisto. There's also the key to the cabinet in the cafeteria (on the floor, in front of the television set by the decayed corpse) -you need the holotape before you can activate the robot. You can 'test' Fisto before telling it to go back to the Atomic Wrangler. The screen goes dark and you can hear a peculiar drilling sound. After the 'testing' has ended, your character experiences numbness, which 'is normal'.

Behind the scenes
The name of this quest is a reference to the songs "Wang Dang Sweet Poontang" and "Wango Tango" by Ted Nugent.