Thought I’d share some of my favorite items in this list compiled by by Phil Pirrello and Scott Collura.

• In this the original draft of the script, the Empire does not attack the rebel base on Hoth. Instead, Wampas attack and infiltrate our heroes’ icy compound.
• Once Luke is taken captive and turned into a frozen Wampa snack, the original draft deviates from the movie we all know and love. How so? Gone is the Jabba-Han subplot and the bounty hunters, and in its place is Solo going after his stepfather, a man named Ovan Marekal. Ovan is a huge political bigwig who’s carefully aligned himself with Darth Vader to protect the people of the galaxy. The Rebels believe that if Han can get to him, he may be able to convince him to fight against Vader, giving the otherwise helpless Rebel Army a fighting chance. Some of Ovan’s backstory would find its way into the character of Lando in the final film.
• Cheers barfly and frequent Pixar voice actor John Ratzenberger had a cameo as Alliance field officer Major Bren Derlin, stationed at Hoth’s Echo Base. You may remember him as the trooper who tried to talk Han Solo out of riding off in search of a missing Luke Skywalker. “Your Tauntaun will freeze before you reach the first marker!,” he shouted. To which Solo replied, “Then I’ll see you in Hell!”
• Alec Guinness is said to have shot all of his scenes in six hours.
• The scene in which a swamp creature grabs R2-D2 was filmed in George Lucas’ unfinished swimming pool.
• After the swamp creature spits out R2, Luke – in the original theatrical cut – says, “You’re lucky you don’t taste very good.” In the Special Edition, the line was changed to “You’re lucky you got out of there.”

100 Things You Didn’t Know About The Empire Strikes Back – Movies Feature at IGN.