Ferrofluid is the oily substance collecting at the poles of the magnet which is underneath the white dish Nokia is bringing tattoos into the high-tech world. The telecommunications giant recently filed a patent for the world's first smart tattoos. Made of ferromagnetic material, the tattoo would vibrate when your smartphone received incoming phone calls, texts and emails.

The tattoo is either cool or creepy depending on your attitude toward such things as tattoos and cyborg implants. But human cyborg technology is nothing new. Indeed, Nokia's vibrating magnetic tattoos are part of a broader trend in technology. No longer content to carry gadgets, there's a movement toward getting the conveniences of smartphones and other electronic devices embedded right in your body.

Google's augmented reality glasses are one example of this trend. While the technology isn't there yet, Microsoft is actually working on augmented reality contact lenses as we speak. Such technology would allow you to, for example, read the Wikipedia entry for a building you came across while traveling, or give you real-time directions to your favorite restaurant or bar. 'Interface scaffolds' hold great potential for amputees, wiring their prosthetics directly to their nervous systems, a tech with unlimited potential for non-amputees. Cyberdyne offers a robot suit, dubbed the hybrid assistive limb, currently available for rental in Japan, with applications for the workplace, such as aiding in heavy lifting. Silicon.com called cyborg brains 'the next evolutionary step.'

Ferrofluid on glass, with a magnet underneath Still, a tattoo embedded in your skin to receive calls holds neither the medical necessity of interface scaffolds, nor the pure practical abilities of a robotic suit. Nor does it enhance your quality of life in quite the same way as an augmented reality contact lens. All that a vibrating tattoo is going to do is have you not missing phone calls and text messages that you might not otherwise get. It's not clear that the market interest is there. While certainly a curiosity, the smart tattoo seems to have a very small niche market existing in the intersection between body modification aficionados and people who always have to have the latest gadget the second that it comes out.

Nokia's tattoo utilizes ferrofluid, liquids that become heavily magnetized when a magnetic field is present. Made of ferrous materials at the nanoscale, ferrofluid is used in everything from aerospace to art. Still, one problem with Nokia's patent is that no one has applied this technology to the human body in quite such an intimate way as of yet. The long-term effects of such technology are more or less impossible to gauge. This makes the first generation of early adopters guinea pigs for the technology, another reason that Nokia's smart tattoos might not be very marketable.

Also impacting the attractiveness of such technology is the ability of human beings to unplug from their gadgets. Certainly, you need some way to shut the tattoo off when you're sleeping. But in an age when people are increasingly plugged in -- and sometimes seeking ways to be less so -- it's not clear that even tattoo-loving gadget hounds are going to queue up for a tattoo that wires them to the information super highway 24 hours a day, seven days a week and can't be removed without painful surgery.

A ferrofluid in a magnetic field showing normal-field instability caused by a neodymium magnet beneath the dish It's also important to ask oneself what happens if the tattoo begins to malfunction. Can the tattooed person have it removed in the same manner as a standard, ink-based tattoo? What methods will exist to resolve end user problems in a vibrating smart tattoo gone haywire? How will the end user deal with a tattoo that won't stop vibrating as he waits for customer service to resolve the issue?

None of these problems are insurmountable in the least. One thing that the innovation community firmly believes in is the ability of human beings to resolve problems once they have been identified. Still, the bigger issue is the one of bringing the device to market. Contact lenses can easily be removed and can greatly enhance the experience of traveling. Vibrating tattoos seem very gimmicky, without much appeal to a broader market. Interesting to think about and cool to read about, there's not much of a chance you'll see this one coming to a Radio Shack -- or tattoo parlor -- near you any time soon.