One of the many books that attempts to pad out the new universe inhabited by Star Wars: The Force Awakens has given enthusiasts a hint of a deleted sequence from the film, one that would've expanded upon the... [SPOILER]
...the scene in Maz Kanata's castle where Rey finds some old box in the cellar that has one of those magic wavy LED swords inside it and has her weird mental moment. According to a paragraph from book Star Wars: Rey's Story, there was supposed to be more to the weird flashback/vision/hallucination thing she experienced when touching Luke's sabre.
The book hints that the original plan was to show us a snippet of the Vader/Skywalker lightsabre battle inside The Force Awakens, expanding the vision scene with:
"As she peered into the distance, she saw a man in black wielding a red Lightsaber. His face was covered with a mask, molded to approximate a human face. But the mask’s eyes were dead and empty. The man’s red Lightsaber clashed against a brilliant beam of blue. A young man with blond hair raised his own Lightsaber and fought furiously against the monster in black."
That's from the novelisation of Rey's side of the film, one presumably written before the decision was taken to drop the sequence from the final film. So that's one for the Blu-ray release. [Making Star Wars via Den of Geek]