This is a "bottle episode," an episode with limited cast and sets produced due to limited budget. The show had spent much of the budget on the building of the superlab, so a low-cost episode was needed.
Rian Johnson has the distinction of directing both the lowest-rated, Fly (2010), and the highest-rated, Ozymandias (2013), episodes of the show.
Walt's shoe hanging from the ceiling is a reference to the common urban legend that shoes hanging from wires indicate a drug dealers' meeting point.
The filming of the scene where Walt falls from the railing utilized a unique process. A stunt double initially fell and members of the crew took pictures of his landing. Cranston then assumed the same exact position and close-ups were taken of his face.
This was voted by Watchmojo.com as the single best bottle episode ever made; however it received the least favorable rating (7.8) in the entire series by over 34,000 IMDb contributors.