KOP,
One of the things that stood out in my wife's mind (besides that they filmed all of her scenes in an abandoned shopping mall in Inglewood as a stand-in for Tokyo) was the racing scene in the parking garage.
All the extras were told to make waiving up-and-down motions as the cars approached and went by, but in slow motion 1/3 to 1/4 normal speed. The cars were actually only going about 20 to 25 mph, but when the footage was speeded up, it made them look like they were going 80-100 mph. So the crowd had to be "synched" to the action to make it look right, otherwise they would have looked like they were on 20 types of speed.
With overtime, as they went over all but one day, I think she ended up clearing about $90/day. Oh, and she did say that craft-services put out some really tasty quality food for the crew, including the extras - they got the same food as the stars.