Just stumbled across (in the traditional sense of the word not stumble upon) the feedjit site after checking out this rather interesting real time traffic map.
There's also one of those 'popular pages' widgets that you see more and more on sites these days - see image.
It won't work on every website in the world, the widget has to be able to get the information from your website - therefore it works with blogger, typepad and the open source version of Wordpress (but NOT Wordpress.com).
There's so many widgets out there and most of them are utterly pointless and not even slightly amusing. However there's no doubt in my mind that the 'recommended reading' and 'popular pages' widgets are really useful - it's just another way of highlighting other areas of your site to your users.
The live traffic map may be less helpful but i clicked on it didn't I?!
Online popularity culture is killing good journalism
Manipulate the BBC's most emailed stories