I learned this from alex on game faqs. During the atlas challenge. After the saw room you go up the steps. Kill the first 2 harpies, but not the one below the tower you are bout to enter. Go inside you have to pin him between you and the ladder and kill him with   triangle move so he dies just above the ladder and get caught in the fall. He will bounce for 15 ,20 minutes and give you oooohhh soooooo many orbs..allowing you to get all upgrades.
Added by: lisa contis Aug 27th 2008, ID#30801