Go to the fight scene in the subway. Right after the infamous "Neo's wires" mistake (up above). Right after Neo lands Agent Smith gets up and reaches for Neo. Look at the graffiti on the wall. There is a "hewlett packard" sign and some white scribbling. Just before the subway hits the agent, red scribbles are added, more white scribbles, and even a faint duplication of the hewlett packard sign.