The Legend of the Star

 is a quest in Fallout: New Vegas.

Quick walkthrough
Collect 50 Sunset Sarsaparilla star bottle caps and deposit them in the machine, Festus (Fallout: New Vegas), in Sunset Sarsaparilla Headquarters.

When first approached by Malcolm Holmes, the trader who informs you of the value of the Star caps and tells you about Festus, you can kill or pickpocket him to take his 7 star caps. Killing him has no loss of karma.

You may encounter a gun battle between Tomas and Jacklyn outside of the entrance to Nipton. This appears to happen at any point in the game. If Tomas survives he will tell you he was attacked by the woman he'd been traveling with, who wanted the necklace that he made from the Star caps. You can persuade him to give them to you if you pass a speech check of 50, or just kill him and take the necklace. It will net you 7 more of the Star caps. 2 more star caps can be found on Jacklyn's corpse. If Jacklyn survives the fight, she will come running and ask you if you saw a maniac running around with a gun, saying he was chasing her and mumbling something about star caps. This is a trick: she is the one who's searching for Star caps. She'll turn hostile just after talking to her. Kill her and take her caps - she should have 9 on her: her original 2, plus the 7 she took from Tomas. Also outside of GoodSprings is a shack that has 1 star cap. It might not seem like much, but there is a key on the desk that lets you open a locker in the back that has ammo and guns.

At some point after collecting 50 Star caps, another collector might come to assassinate you. You can kill him and take his 8 star caps.

Detailed walkthrough
A simple way to get around the star bottle caps is (if you have the caps) simply travel to Nellis Hangars and buy 30 sunset sarsaparilla off the chef every 3-4 days stock up a large amount and hope luck is on your side and you get all 50 for the information. There are also 2 star bottle caps on a table in the Nellis Hangars Mess Hall.

In order to complete this quest you need to find 50 Sunset Sarsaparilla star bottle caps and return them to Festus. Festus is located inside the Sunset Sarsaparilla headquarters, which is south of The Thorn and east of Jacobstown. Upon completing or failing this quest it unlocks another quest.

Once you give Festus 50 Sunset Sarsaparilla star bottle caps, he will tell you the story about the drink. After he is done it will say quest failed, but it gives you another quest: A Valuable Lesson.

Sunset Sarsaparilla star bottle cap locations.

Bugs

 * Depositing 50 Star caps into Festus, which will end the Legend of the Star quest, will also shut Festus down permanently. This means you will no longer be able to play Festus' game "Lucky Horseshoes" for its occasional Caravan card prizes. (**NOTE Can still play Lucky Horseshoes on PC version 1.2.0.285. **Note: PS3 version fixed)

Behind the Scenes
According to JE Sawyer, the quest was inspired by his experiences collecting Tootsie Roll Pop wrappers as a boy due to an untrue rumor that sending 100 special wrappers which had illustrations of a boy dressed as an Native American shooting an arrow at a star would yield a special prize. The story Festus tells upon completion of the quest is based upon a story that was sent out to children who sent in wrappers and shares many common elements.