What is hidden in 3D image?

Reaching the end of a job interview, the human resources person asked a young engineer fresh out of MIT, "And what starting salary were you looking for?" The engineer said, "In the neighborhood of $125,000 a year, depending on the benefits package." The interviewer said, "Well, what would you say to a package of 5-weeks vacation, 14 paid holidays, full medical and dental, company matching retirement fund to 50% of salary, and a company car leased every 2 years - say, a red Corvette?"
The engineer sat up straight and said, "Wow! Are you kidding?" And the interviewer replied, "Yeah, but you started it."