Large whiskey bottle (Fallout 3)

The large whiskey bottle is a common item in Fallout 3 and Fallout: New Vegas.

Fallout 3
It's useful only as Rock-It Launcher ammunition. They can be found in every settlement and many ruins.

Fallout: New Vegas
The Honest Hearts add-on introduced a recipe for Large Wasteland tequila which requires this item, making it significantly more useful.

Fallout: New Vegas
Large whiskey bottles can generally be found in areas with large amounts of Empty whiskey bottles, only in smaller numbers.
 * Two are found right next to the campfire near the Goodsprings Source fast-travel point.
 * The casino area of the Lucky 38 contains a full dozen on a set of shelves behind one of the counters.