Experiment: a brief history of favicons
I've been using MeeTimer's SQLite database to track my browsing for about a week. Now there's some decent data to play with, I've cobbled together some PHP to render a Canvas element visualising the previous 6 days' history.
(Time shown is GMT rather than BST)
Here I'm just showing the favicons for a dozen sites I seem to visit (very) regularly (e.g. Twitter, Gmail, Flickr, Google, Technorati, Feedburner, Google Reader, Delicious, etc...). The size of the icon is proportional to the length of the visit.
There's also a more detailed chart which shows all visits (but without the cute icons)