Happy to land a job, especially in this market, far too many workers are doing themselves a disservice not asking for more money. "One in five people never negotiate" their salary, says Jim Hopkinson, a marketing director at wired.com and author of SALARY TUTOR: Learn the Salary Negotiation Techniques No One Ever Taught You. That's as silly as buying a used car without haggling over the price, Hopkinson tells Aaron Task in the accompanying clip....