Fans like this are being used on some server rack chassis now. They are quite popular due to the lack of noise, and the fact that they function by creating a toroidal effect suction which lets them move quite a bit of air. Dyson is making an (overpriced) smaller version that you can buy at many big box stores.

The down side is that they in fact are not bladeless. The blades are inside the circumference, moving at high speeds, to produce the toroidal flow, and while they create very little friction and even less noise, they tend to be dust magnets and can be a pain when they clog up.

It's an interesting take on airflow, but still a little immature for popping into your PC. Give it a few years to get figured out.

There is a detailed diagram of their fan design on their website. They are literally just flat rings. There is no blade I can perceive. The only additional turbulence outside of the air friction to the flat rings comes from the pegs that connect all the rings.

It's not a "blade" as we are thinking of normally. The rotating segment itself is the blade, and the air is drawn through friction, which forms the toroid (in at the narrow edge, out at the wide edge).

Blade -

• The flat cutting edge of a knife, saw, or other tool or weapon.

Fan -

• An apparatus with rotating blades that creates a current of air for cooling or ventilation.

Clearly it meets both definitions, however, I think we can at least agree that it does not use traditional curved blades to scoop the air.

Nice! Interesting concept, thanks for sharing the video!