We use them in industrial scale. They were around way before this Dyson character.
They are called air movers, we use much Brauer.
http://www.brauer.co.uk/standard-fixed-gap-s386.aspxI hate the touch.pad. Just deleted a long story.....
They are pretty handy if you require a small lightweight unit that you put next to use point. They need careful design and dimensioning. Poor economics on continuous use. You need to consider pressure ratio, but if you need hits the curve they work.
They are great if you need small scale underpressure or you have allready a good compressed air system and you need intermitently some means of moving air (under pressure).
Just one thing. They are very particular about the "cap" they look very simple and there might be a urge to see what it ate.
PekkaNF