The repeated statement "bottle episode" refers to the term used in episodic television for episodes which are produced using the least money, and restricted in their scope to use as few or no non-regular cast members, effects, and sets as possible.
The second time that "Beetlejuice" is said, in reference to Jeff's underwear.
Britta's line, "Welcome, my friends! Welcome to the machine!" after her purse is emptied, is a slightly reworded version of the opening lines of Pink Floyd's song 'Welcome to the Machine' from their album, 'Wish You Were Here' (the song says "Welcome, my son").