I just updated the Strength Workout Calculator. It now computes the amount of calories expended in the workout and the total amount of pounds lifted. For calories expended, it needs to know which lift you are performing, since the bar moves different distances depending on the lift. I used some measuring tape and my body 5'11 to estimate the bar distances for the various lifts.
I learned some interesting facts while making these improvements. According to Wikipedia, human muscles are about 20% efficient in the context of aerobic exercise (biking, rowing) meaning that the mechanical work is multiplied by 5. Even so, surprisingly few calories are expended. Take for example a 200lb deadlift workout starting at 65lbs expends about 8 calories in total while moving 2,975 pounds. Let me tell you, it feels like a hell of a lot more than 4 goldfish crackers worth of work! So the "calculations" need to be taken with a huge grain of salt.
Of course weight lifting for strength training is the opposite of aerobic exercise and I believe the 20 percent doesn't take into account the amount of energy expended to repair those muscles after the workout, which I imagine to be significant because heavy deadlifts make me hungry for a large steak.