At the end of the film, Wyatt and McQuarry each take a briefcase containing $5 million dollars. $1 million dollars in $100 dollar bills (highest denomination in circulation) weighs approximately 22lbs = 110lbs for $5 million. $5 million in $100 dollar bills is also approximately 3445 cu. in. in volume. This would not likely fit in the cases they are carrying, and would not be as easy to carry as they are.