What should hyperlinks do? What attributes should they have?

[pollarda@xxxxxxxxxx (Art Pollard)]

I've been giving a fair amount of thought lately to allowing hyperlinks 
to have attributes.  This of course, also implies that they have the 
ability to do other things besides "link".  For example in HTML, it is 
possible to link to an image.  (i.e., the link in this case had an 
"action" associated with it -- start up the GIF viewer and display image 
X) 

Some of the attributes I have come up with for links are as follows:

Author
Creation Date
Title
Comments
etc.

Some actions associated with links I can think of are as follows:

Launch a script (or other program)
Highlight a phrase.
Perform a query.
Simply jump.

What other attributes and actions might/should links posess? I envision
that links should have a fair amount of structural information to them
(much in the same way a document would).  Some might argue that links
should be fairly minimalest and only link.  However, I disagree as the
links themselves in many ways become part of the document and thus (like
different parts of a document) need to serve a wide variety of functions.

How robust should links be?  What attributes should they have?  What 
actions should be associated with them?

-Art