I'm thinking of using some highly simplified cloth physics in my next game for things like capes/cloaks/hair/flags etc. I couldn't find anything very useful on Google, maybe I'm searching for the wrong thing. Does anyone know where I could find some tutorials for this sort of thing? OpenGL would be great, but even articles which explain the theory would be good.

There's an article on Gamasutra that shows the easiest approach to a physics engine(including cloth simulation) that I've seen.

I've actually implemented the basics of that article (particle system, Verlet integration, particle collision & response) in the last couple of days. If anyone's interested in the (hack-ish) source, email me.