Using Arsenic to Build Cells

This article http://www.wired.com/wiredscience/2010/12/nasa-finds-arsenic-life-form/, talks about a group of scientists that coaxed a bacterium to use arsenic in place of phosphorus as an elemental building block. There is some debate regarding the findings, but if the bacteria really are using arsenic as a building block, then this would be a scientific first. Arsenic is right below phosphorus on the periodic table of elements, which means that the two elements share some characteristics, although arsenic would normally destroy any cell it came into contact with. To be honest, I wasn't too surprised at the finding. It fits with my concept of an alternative world in which the infinite possible permutations of life are allowed to exist due to a hypothetical absence of influence. The bacteria normally exist in an extreme environment in which certain mutations were strongly selected for, then the scientists altered their environment further, allowing other changes to occur that might not have normally taken place. It raises the question of what other weird things life could do in an artificial environment in which the normal rules of biology are tweaked.