There are several different organizations that publish “Best of the Web” lists each year, recognizing different governments for innovation and the appropriate use of web technology. The Center for Digital Government is one such organization, and they provide links to pages they rank highly. You can see their latest rankings for 2012 here; 2013’s will be announced this fall.
It’s important to note that they score sites on a variety of factors – not all their top sites look the same, and in fact they may take dramatically different approaches to how they look and feel. Government websites are (or should be) reflections of their communities, and this is all the more apparent when you peruse the top listed sites.
If you’re in the planning stages for redesigning your own website, it’s a good idea to take some time looking at what others are doing and comparing what you’d like to see with what’s already out there. Ranking sites like this are a great place to start browsing.