Is there any way to programatically disable cookies being created by a page displayed inside of a frame/iframe? Or to generalise further, is it possible to programatically d
The only way you could change that for an external website you have no control over is to retrieve the pages using a server-side script, filter the input and display it to the user (ie: act as a proxy).
You just can't modify sites out of your domain (or subdomain - it might depend on the browser) using J/S for security reasons.