There's 3 questions here:
1. Does it exist?
No not really as far as i know.
2. Is there a need?
Yes there is. More and more people use cellphones, palms and pocket pc's to access perlmonks (i know i do on a Nokia 6600)
3. How can i make it myself?
Well with a little xml + xslt you could make a html version just the way you like it. I have a sidebar for mozilla that uses the newest nodes xml generator and an xslt file to be rendered by the browser. It might inspire you. Here's the link: Perlmonks.org Mozilla Sidebar.