Nope. Such changes are purposely banned by the W3C for security reasons. The following are not allowed:

- The website cannot read or change properties or objects which did not originate on its own server.

- Websites cannot set properties on file uploads.

- User confirmation is required for a website to send an email or post a message.

- The website is not allowed to close windows it did not create without user confirmation.

- The website is not allowed to snoop in the cache or the rest of the user's computer.

- The website cannot create windows which are not visible, or windows without a title bar.

- The website cannot alter computer settings without user permission.

- The website cannot change security settings.