In string theory, one of the many vibrational states of the string corresponds to the graviton, a quantum mechanical particle that carries gravitational force. Thus string theory is a theory of quantum gravity.
Their average web application development cost is around $500K and their staff or contractors' salary is in the six figure plus range. Their proposals are usually based on a lot of fluff with the development rate ranging from $400 - $800 per hour. These types of companies focus on custom development.
In my experience, I've known web/graphic designers and illustrators to charge anything between Â£20-Â£60 per hour; web/software developers between Â£25-Â£90 and copywriters to charge from Â£20 to Â£50 per hour.