I’ll go first.
Winner:
Breaking Bad, season 3 episode 10, “Fly”
Honorable mention:
Community, season 3 episode 10, “Cooperative Calligraphy”
PS: I’m having a hard time categorizing these as real bottle episodes since they don’t feel cheap or “fillery” at all, but they are at least spatially and plot wise confined.
Red Dwarf - Marooned
Only because OP took my 2 favourites already.
TWELVE? Twelve years old? You lost your virginity when you were twelve?
Yeah.
Twelve? You can’t have been a full member of the golf club then!