Viryd is a spin-off of Fallbrook Technologies, which makes continuously variable transmission (CVT) technologies for bicycles. Installing a CVT on a bike allows for smooth and infinitely variable gearing, rather than a standard number like 10 or 21 gears.
Gearing changes are a point where energy is lost in standard transmissions, which makes the CVT a natural fit for a power generator with unsteady input like a wind turbine.
Trying to improve on the wind turbine market is far less common than other clean tech innovation, though. Commercial wind power is typically considered a somewhat more "mature" market, with a well-understood and developed technology without a lot of room for new innovation.
The $2.1 million funding came from private investors, and was reported by VentureWire (subscription required). Viryd is in the process of moving to San Antonio, Texas.
For the gearheads, here's more, from a Popular Science article, on exactly how the original Fallbrook technology works:
"Twist a dial on the handlebar, and ball bearings in the bike’s NuVinci transmission tilt between two rotating metal discs. (Your pedaling turns one disc; the other transfers power to the rear wheel.) As the balls tilt, they touch the discs at varying angles. This changes how fast the wheel spins relative to your pedaling—slowly for low gear ratios, where pedaling is easy but the wheel doesn’t turn much, and quickly for high ratios. The balls can roll to almost any angle, giving you precise control over the bike’s torque..."