What exactly are the varying techniques, others have used, for creating wind? There isn't much talk about it and a search gives me 5000 hits because of the word "window".

I'm trying to develop a wind system that is totally random..somthing fast and somewhat simple that will affect models. Say I want a hanging light or a tree to sway in the breeze, but the sway should be totally random and dependent on the wind direction(and changes in direction). I suppose it could be coded for each entity as an action and assigned to the individual entity, but I like the idea of a global wind that is independent of the entities(or is it?) for whatever insane reason.

This almost sounds like a physics issue, though I haven't dove into that crazy place, yet.