Submit a delicious user name and generate an OPML file that links to feeds for each tag:
<outline type="feed" text="userName/thisTag" url="http://del.icio.us/rss/userName/thisTag"/>
one for each delicious link item.
You can also limit the display to tags that have more than a specified number of links bookmarked to that tag.
For more fun stuff, check out OUseful.info.