The Moon Comes Over the Tower

 is a quest in Fallout: New Vegas.

Walkthrough

 * Speak to Emily Ortal near the entrance to the Lucky 38 to begin the quest. She will ask you to bug Mr. House's mainframe. If she doesn't appear outside the Lucky 38, the player needs to progress further in the main quest line. It appears from the scripts that the player needs to kill Benny or initiate combat in The Tops in order to get Emily to appear.
 * Enter the Lucky 38 casino.
 * As you enter the main casino, turn left and head up the stairs to the VIP lounge.
 * Activate the terminal behind the bar.
 * Choose the option to bug the network.
 * Head back outside the casino. Emily should be at the bottom of the stairs or immediately to the left (near the gate to the next part of the strip).
 * Tell Emily you bugged the network, she will tell you that this data "might come in handy".
 * However, after that, the reports stop coming in (due to Mr. House removing the bug).

Reward

 * +600 XP
 * (5) Stimpacks
 * (2) Doctor's Bags
 * (2) Super Stimpacks
 * (2) Med-X
 * (2) Today's Physicians
 * Followers of the Apocalypse fame

Bugs

 * After completing the quest Emily will remain outside the casino and you can talk to her to learn about the first attempt on hacking Mr. House's network. A 35 speech level dialogue option eventually becomes available that will remain in the dialogue list even after granting the player the reward for selecting (experience, completion of speech towards challenges). This allows the player to get credit for completing speech challenges (the experience points for completing the speech option is only given once however). Note that ending the conversion will block any further communication (and thus exploitation) although Emily will remain in front of the Lucky 38.
 * Emily may enter the Lucky 38 to present this quest, when doing Act II before doing Act I.
 * Emily approached this player in the middle of another quest, in another part of the Mojave in order to ask if I had bugged the Lucky 38 yet.
 * You can still get the quest after killing Mr. House, it does not change dialogues with Emily. (tried twice on PC version and once on Xbox 360)
 * Even if you have installed Yes Man on Mr House's computer system, Emily will still tell you Mr. House disabled the bug 30 seconds after installing it.

Behind the scenes
"When the Moon Comes over the Mountain" is a popular song published in 1931 and written by Howard Johnson, Harry M. Woods, and Kate Smith.