developed in Canada. It also used the Coanda Effect and was predicted to be able to take off vertically and reach supersonic speeds. Unfortunately, it never was able to fly higher than 6 feet high and the top speed was, well, much more modest than predicted. (More info here). The Avrocar was a failure as an aircraft but may have been the first hovercraft.

If all you want to do is hover, then perhaps a circular vehicle based on an improved application of the Coanda Effect might be the ticket. However, if you're interested in forward flight, you quickly run into some aerodynamic problems. The vehicle has a thick, low aspect ratio wing with a very blunt trailing edge. Keeping the airflow attached across such a wing is difficult and drag at high speeds would be high. In addition, it has a poor lift to drag ratio, especially at low airspeeds. This hurts acceleration and climb performance. Whether that's a serious problem or not depends on your intended use. As a UAV to fly around an urban area, it might work very well.