The parents of Rachel Corrie, a 23-year-old American student who was run over and killed by a Caterpillar bulldozer in Gaza in 2003, have filed a lawsuit against the bulldozer maker...In a statement, Caterpillar said: "...more than 2 million Caterpillar machines and engines are at work in virtually every region of the world each day. We have neither the legal right nor the means to police individual use of that equipment."