Dave, you've been beaten to the whacky lifters:
http://jnaudin.free.fr/lifters/main.htm
It works by electrostatically accelerating air through the grid, but not sure about thrust/power efficiency (probably quite good). It could be scaled up, but by the time you have a turbogenerator supplying power and high voltage equipment it may have been easier/cheaper to drive a rotor head. I notice none of them lift their own power supplies yet, although perhaps with a low enough "grid loading".
This is the problem with all these approaches to generating downforce, very little approaches a rotor in terms of weight for a given planform area. There is then the same problem as a ducted fan that you end up with high disk loading, so a compromised machine. This puts these ideas firmly in the dreamers catagory, but the practical folk won't touch them. JL Naudin has done some serious work though, both in experimental work and documentation of the technique.
Trouble is JL Naudin also gets into all this over unity energy stuff, which always looks interesting at first but later ends up having overlooked something. Wonderful if a "box" could generate power from mystical quantum phenomena, but i just don't buy it. Partly because physics has taught me that you don't get ought for nought, and partly because as an engineer i have to eat.
For completeness i include the main site (with coanda effect aircraft):
http://jnaudin.free.fr/ This is a helicopter pilot's forum, so i will not discuss anything else further. There is the usual combination of fun and certifiable...
Mart