power-line mounted turbines?

Check out this winner of the 2008 red dot design awards by Nils Uellendahl, it's a concept for a helical turbine that mounts directly onto over-head power lines. It's quite interesting in two ways:

• it generates electricity directly into the line using induction
• It's actually horizontally mounted, however is actually a traditional vertical-axis turbine

I'm sure there are some large issues with the electrical connection and grid stability (to say the least!), and with the additional loading of the power lines, however it's a great concept.