Austria's Beck Fastener Group, which manufactures metal nails, staples, screws and pins, have developed wooden nails that can be fired out of a nailgun. Their Lignoloc system uses beech wood that has been compressed using a proprietary method, yielding something that resembles a golf pencil without the lead; these are then collated and fed into their specially designed Fasco F44 nailgun.
When fired into wood, the high speed of insertion and resultant friction causes an effect called "lignin welding," whereby the heat essentially welds the nail in place.
The company is targeting Lignoloc at "industrial production and ecological timber construction." Advantages touted are that the fasteners don't leave rust streaks, no pre-drilling is required, no glue is required, you can run a sander over the surface without tearing up the pad, and can trim fastened pieces as needed without running your sawblade into a metal nail.
I'd think these would also be great for attaching floorboards to joists, with an eye on future maintenance; you could sand and refinish the entire floor without having to first hammer existing metal nails below the surface.