The smaller the hypodermic needle, the less it hurts when it pierces skin.That leaves about 3 more years.
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Microneedle-based devices could be on the market within five years, according to the researchers. The work appeared in the November 17, 2003 issue of the Proceedings of the National Academy of Sciences.
There's also [link|http://www.aip.org/radio/html/painless_shots.html|Ultrasound Painless Shots]