Deckard: I don't know why he saved my life. Maybe in those last moments he loved life more than he ever had before. Not just his life, anybody's life, my life. All he'd wanted were the same answers the rest of us want. Where did I come from? Where am I going? How long have I got? All I could do was sit there and watch him die.
When Deckard visits the Tyrell Corporation, he prepares to test Rachel with the "VK" machine. He is shown putting his briefcase of the table and lifting the "VK" machine out and onto the table. If you look closely, the "VK" machine is already on the table and Harrison Ford is miming the lifting - there is nothing in his hands!
At the end, Batty gives his 'a time to die' speech on the roof. Rutger Hauer made up the speech himself, between an hour and half an hour before filming the scene.