Here's the first example I've come across:
https://www.kickstarter.com/projects...tm1-3d-printer
They claim it is "Capable of printing 0.002-in layers at 200 mm/sec with no loss of dimensional accuracy"
And for the technology"
"So we built a patent-pending motion stage called ServoSpline™, which positions the part under TM1's precision gear-driven extruder head. It consists of two independently-driven pinions that engage with elastomeric racks on the underside of the build plate. The splines guide, support and drive the build plate. Free of the backlash found in most rack-and-pinion motion, the new build platform achieves positioning accuracies better than 0.005-inches at maximum build speed. The ServoSpline design also keeps the number and mass of moving parts to a bare minimum, limiting cost and promoting smooth, accurate motion."