So what does everyone weigh?
Well, let's see...world population is currently estimated at 6,788,969,000.
With newborns weighing as littls as 1 lb or so and heavy adults weighing as much at 400 lbs with some regularity, the mean weight would possibly be around 201 lbs. So the weight of everyone could be very roughly estimated as follows:
6,788,969,000 * 201 lbs = 1,364,582,769,000 lbs or 618,964,332,251 kg.
For comparison, the Earth's weight is estimated at
6,000,000,000,000 ,000,000,000,000 (6E+24) kilograms.
Wow. No wonder the power of the Hayabusa was created!