Online Extra: Sanjay Sarma: Mighty Smart Labels  Forget the bar
code. In a few years, it may be replaced by networks capable of
following products from factory to warehouse to supermarket
shelf. The mastermind behind this system -- called radio
frequency identification (RFID) -- is Sanjay Sarma, a professor
and research director of Massachusetts Institute of Technology's
Auto-ID Center. With the help of dozens of companies and five
other universities, he has cobbled together a network that
hinges on all pallets, cases, and individual items -- whether
packs of razor blades or bottles of shampoo -- carrying their
own RFID tag. He recently spoke with BusinessWeek Boston
Correspondent Faith Arner about the struggle to make the new
system work without breaking the bank.  Q: How did a roboticist
get into RFID?  A: Quite simply I got into auto ID because of my
colleague David Brock. One day he came to me and said, "Why
don't we just put tags on everything and instead of having the
robot recognize with vision? Why no