I'm curious about how this might be accomplished, and I don't mind sharing my reasons. I've got a page that uses jquery to present my semantically marked-up content as tabs rather than a long list of section one below the other. As is common, it does it by hiding/showing the relevant divs, and the 'tab-tops' themselves are a styled, unordered list.
Similarly, if styles are also disabled then the use gets the same thing (list of skiplinks followed by sections in simple linear order), just unstyled.
I can create helpful workarounds for 'js:on, css:off' users who might wonder why the skiplinks don't work, but my options for doing so expand if I can detect whether styles are on or off via js. As far as I can see, none of this contradicts the progressive enhancement ethos; everything is a non-destructive addition to the basic semantic xhtml.
Looking forward to people's views.