The problem with that theory, is that the earth and atmosphere are NOT oppositely charged. The contain both negative and positively charged particles, electrons, photons etc.
When we see a static imbalance, we see lightning. Static charges are easy enough to create, but the problem is they don't carry much current. Or if they do the duration is brief. many, many many people have tried turning it into a controlable, usable charge.
The problem is when you try get WORK out of it. When you apply a LOAD, A static charge will pick a less resistant path.
The web is full of failed experiments, there are millions of useless patents out there. Anyone can patent a useless concept. Check them out here:
http://ep.espacenet.com/search97cgi/s97_cgi.exe?Action=FormGen&Template=ep/EN/home.hts
And this is a good site to look at all the "free energy" attempts over the years.
http://freeenergynews.com/
You can spend a long time looking at this stuff, but in the end you will find that there are basic laws of physics that apply.
cool. Thanks for the links!