I don't think this has been widely acknowledged but Burnell Tucker, the actor who played the character now known as "Del Goren" in Star Wars: A New Hope ("Squad leaders, we've picked up a new group of signals. Enemy fighters coming your way."), also played a character in Echo Base in The Empire Strikes Back known variously as "Other Rebel Officer" (how he is credited on IMDb) and "Senior Controller" (in the screenplay). He's the guy who is listening to the Imperial probe droid when Rieekan tells Han and Leia, "We've picked up something outside the base in zone twelve, moving east." Han says, "It could be a speeder, one of ours" and Tucker's character says, "No. Wait, there's something very weak coming through." I'm confused why this actor, who is playing a very similar role in both films, is not credited as "Del Goren" in Empire as well in the EU. I'm sure it's simply an oversight as it took someone pointing out to me that it was the same actor to notice this. But it's definitely the same guy from A New Hope.