Part of the HTML 4.0 specification includes the TITLE attribute, which can be applied to just about any HTML tag to provide additional information (see http://www.w3.org/TR/html4/struct/global.html#h-7.4.3). In Microsoft IE4 and higher, this is supported by providing a "tooltip" in a yellow box when the mouse cursor is over the appropriate block of text, similar to how the ALT text for an image is displayed when the cursor is over an inlined image. (Netscape 4.x doesn't support the title attribute.)
TITLE="subliminal message">Ooh, a link!</a>
It would be useful to provide TITLE attributes automatically for all hardlinks generated on E2. The text would be the title of the node being linked to, which may or may not (if a pipe link is used) be the linked text. Most hyperlinks on E2 don't need the TITLE attribute -- for instance, a user's name always goes to his home node, and a softlink will always go to that node. But because hardlinks might be piped to a different node, the TITLE attribute could be very helpful, and might even lighten the load on the server by preventing people from clicking on links just to see where they go.
(Yes, I know the location of a hyperlink is displayed at the bottom of the browser window, but it's surrounded there by lots of URL-y garbage which has to be read around, and besides, very long nodes won't display completely in that limited space. A TITLE attribute would solve both of these problems.)