I read an article last year about possibily using ionizing lasers to divert lightning strikes from populated areas. Florida State University has been using rockets and conductive wires to accomplish the same feat for years. The laser idea was presented more as a tool for mitigating injuries and property damage. But if you're going that far, I say why not try to harness it as an energy source.
If you simplify a lightning bolt as a line of current, and have it travel through the center of a conductive loop; you can apply Biot-Savart's and Ampere's laws to model the system as an air-core transformer. And maybe it could be stored using those huge power factor compensation capacitors. With the right materials engineering, I wouldn't be surprised if part of that energy could be stored and sold to the market.
I think the American Gulf Coast would be a prime candidate for this kind of study. Some of these cities average 8 to 16 ground strikes per square km annually (source: **broken link removed**). It's probably a generation away, but if it's useful, I'm behind it.