Experiment: Browser DNA
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)
MeeTimer lets you group URLs into different groups. Here, those groups are displayed in different colours.
There's also a much cuter chart showing the favicons for a handful of sites I visit regularly.