Using the chart at
News: Utah Considers Joining 80 MPH Speed Limit Club I did a quick calculation. In an average sedan, burning $4 gas, you save yourself $5.00 per hour for the extra trip time when you slow from 80 MPH to 60. In a truck, the figure might pass $10.00 per hour.
Those are not really impressive wages for getting hired at, but this is untaxed, with no boss, and it makes life safer and more pleasant while saving wear and maintenance on the car. Not bad for a part-time job where you can come and go as you please. Of course, if you want to "work overtime," and drive 40, your pay rate goes down somewhat, and maintaining the other benefits might depend on wether you can find the right roads.