Multipart response support

I think we should consider including support for multipart responses  
in HTML. Among other things this would provide:

- easy preloading of critical components without using JavaScript

- improved digital rights management of images etc. without using  
flash or other plug-ins. (No need to make such resources directly  
accessible on the internet.)

- a mechanism for hiding scripts and stylesheets from (average) users.

Syntacticaly I think it would involve only a tiny change in the  
specification. We only need to extend src-attributes etc. to accept  
references to internal attachments instead of just URL's.

--
Henrik