Instructions
Play Act 1 in the Middle East and progress through the field until you reach the Downtown area. Hide in the steel can after its previous owner abandons it. Walk, while inside the can, a few feet further until you see two crates and three soldiers firing their weapons.
Send the Mk. II robot to pick up the middle soldier's rocket launcher when he dies. Wait until the soldiers respawn and continue picking up the weapons as many times as you want. Each rocket launcher can be sold for 6,000 Drebin points.
Play Act 4 on Shadow Moses Island. Go inside the first hangar and defeat all of the Gekko robots. Leave the hangar and proceed to the next building. Return to the hangar and fight the Gekkos again. The Gekkos respawn an infinite number of times, and you earn 20,000 Drebin points each time you kill them all.
Play Act 5 on the ship. Progress through the ship until you battle and defeat Screaming Mantis. In the next two rooms, kill as many of the Scarab robots as you want. They respawn infinitely and each kill is worth 100 Drebin points.