Similar to the Google Van for Street View, the Connecticut DOT has two vans mounted with cameras and distance-measuring equipment, to capture a full photolog of every state-maintained road. The interval between photos is 4, 5, or 10 meters depending on what's needed. They've been doing this since 1973.
What's cool is that they've started putting these logs (the forward-facing photos) online, in streaming video.
http://www.ct.gov/dot/cwp/view.asp?a=1617&q=439946The quality's better than Street View, but you can't rotate the POV. There are "file markers" in each video so you can jump to a point of interest.
The route selector lists all signed routes, but many of them aren't linked up yet; selecting them and pressing "Go" has no effect. Currently, photologs are online for all US routes and interstates, as well as state routes 2 through 73. Do a "view source" on the page to see what's available.
One of the benefits ConnDOT cites for the logs is being able to review a location without driving out to it. That helps for us too; we can find out definitively how the north end of
CT 71A is signed (not at all), or where the signs for Truck CT 22 are posted (some on US 5 NB near CT 40).