The SharePoint Site Usage Report shows aggregate SharePoint usage by Site. It is a great report to get a sense of what sites are the most active. The report shows a list of sites and then core statistics on Page views and visits as well as storage data.
To table has columns the name of the site, the number of Page Views since data collection began, the number of Page visits since data collection began and some storage info.
As with all of the reports, this information can be customized, filtered and scheduled.