Here’s an interesting visualisation of data from the National UFO Reporting Center (NUFORC): the National UFO Sighting Mapping, Analysis, and Tracking Integration Cybersite maps reported UFO sightings on a map of the United States and the border provinces of Canada. This video is a collection of 14-day “density” plots for 12 months from March 2010 to March 2011 (red indicates a lot of sightings, through to purple for few sightings).
You can ‘drill down’ into the actual sightings at the NUFOSMATIC website.
You can also read (and see) more about NUFORC in this recent Seattle Weekly profile of the man behind the organisation, Peter Davenport.