Embryonic stem cell uses?

Perhaps our future.: A human embryo consists of 50-150 embryonic stem cells 4–5 days after fertilization, and those few cells eventually differentiate into all of the different specialized cells that compose the entire human body. Since those stem cells can potentially be anything they want to be, the potential for curing multitudes of human disease, using them, is enormous.

Value of ESC's: The greater value of the embryonic stem cells as mentioned in another response- is that they are undifferentiated, and can become a multitude of tissue types. In addition- they have not yet "learned" self from not self. So these cells can be used in anyone without creating rejection. In addition - they can be directed to be a particular cell type. i.e. it can be an eyeball, a liver- etc.