If you go to the new Ricky Gervais vehicle The Invention of Lying, keep in mind that the $9.75 you fork over isn't all you're paying to see this movie. I'm not talking about any popcorn purchases, but about the generous tax credits Massachusetts gave the film's producers for shooting in Lowell. When I interviewed producer Lynda Obst last spring, I learned that our tax dollars — we're on the hook for several million dollars for this movie — did indeed stimulate job growth. Unfortunately, the new jobs primarily went to people from California.