The best one I have seen is in the center of Santiago, near MacDonald's. I don't know the name, but it is half a block south (toward the monument) on Calle del Sol on the same side as MacDonald's. They have flash connections for 15 pesos per half hour. Unused time can be carried forward for 2 weeks or so. Your tracks are erased. Best of all, it's air-conditioned. They also have a couple of telephones where one can call the States for about 3 pesos/minute.
No food or drink is served.