Cloud Busting is featured in the movie The Fisher King. You lie on your back and stare up at the sky, and try to break clouds apart with your mind. The main characters partake of this pastime at night in the middle of Central Park in New York. Robin Williams' character claims that you have to be naked to do it correctly... naked!

From the "A-Z of Modern Paranormal Phenomena"
http://binky.paragon.co.uk/paranormal-az/index.html

"Cloud-busting is a supposed feat of psychokinesis, in which clouds are made to disappear by the concentration of thought and will. One of its most famous exponents is Dr Rolf Alexander from New Zealand, whose apparently successful attempts at dispersing fairweather cumulus clouds over Holne Tor, Devon, in 1956 were filmed by the British media. Sceptics, however, commented that this type of cloud usually disappears in 15-20 minutes anyway."

From "How to bust Clouds"
http://www.geocities.com/Paris/Metro/4062/teach.html

How To Bust a Cloud!

Step One.

Find a suitable target cloud, not too big but big enough so that it won't naturally, disappear into the air. Also try and find one separate from the main bank of clouds.

Step Two.

Center your concentration on the middle of the target cloud, keep it there and don't let it wander! The more solid your concentration, the quicker the cloud will dissipate.

Step Three.

After a few minutes, the cloud will begin to dissipate, sometimes it will not completely dissipate, but usually the whole thing will go, interestingly enough, you seem to be able to target your concentration onto a very small area, making it possible to "sever" parts of clouds or seperate large clouds, above all "practice makes perfect" Don't be discouraged if you don't get total results straight away, it will take time to perfect.