Verichip

Another story, this time in Forbes, works to paint a picture for prospective buyers, investors and "chipees" about the benefits of Verichip's sign of the beast implantable RFID tag.

More than 1,000 Americans have already volunteered to get a
microchip about the size of a grain of rice embedded in their arms.
The chip -- similar to those now used to identify thousands of pets
nationwide -- allows EMS and ER crews to gain quick access to
patients' medical e-files should they be unable to provide
them.

Out of a population of almost 300 million, their adoption rate is pretty low, especially if you figure a 200 bed hospital sees 6,000 to 7,000 discharges and around 20,000 emergency room visits per year. To their credit they hit the tinfoil hat crowd's objections head on:

While the technology sounds like a win-win for everyone, it does
have its critics -- namely privacy advocates who worry the embedded
chip could lead to a "Big Brother" state where computers
track an individual's every move.

But [David] Ellis [corporate
director for Planning and Future Studies at the Detroit Medical
Center, and as co-founder of the Michigan Electronic Medical Record
Initiative] believes those fears are unfounded.

"First of all, the chips are voluntary, and we believe that
they should always remain that way," he said. "This
technology is also very easily removed if anyone later changes
their mind about having one."

He also noted that scanners can only read the chips from
distances less than a few feet. "You can't be tracked by
satellite," Ellis said.

Finally, "all that can be read on the chip is that ID
number," he added. "So it requires that someone not only
be able to read that ID number but also have access to the database
that matches the ID number with the actual patient name and
details."

Sadly, I could be easily refuted each of David's points (network effect, choke points, national patient identifier) and I don't even have a tinfoil hat. But don't count Verichip out; their ability to win proponents like David, John Hamalka, and Tommy Thompson (who still hasn't fulfilled his promise to get chipped) is amazing - so is their ability to get hospitals to sign on and get readers.