ListBrowser is another project from Dave Winer and shows functional simplicity as expected. The main screen is the logo above and a simple box asking for the username of the list owner. You are then presented with, well thinking of it, a list of lists for that person. Clicking on any list brings up a simple view of members, the number of followed and followers for each person as well as their bio and links to them and the list itself.
The XML for the list is available and clicking on any user in the list then gives you their lists. The idea became clear. I like this person and they have a good list. Up pops who belongs to that list and clicking on any member shows you their lists. You can basically use this to jump around for hours finding good content and lists themselves. If he adds in tag searching of some kind for the lists, it would be even better!