The trailer is for the Google Street View trike. Google use the trike to take images where the cars can’t go but where a bike can go.
At this same location we also get to see the inside of the trailer:
Similar Street View images
Google crew trailer
Behind the scenes (From Stetson University)
Google team getting ready to leave
Car crashes into trailer
This kid’s happiest (and most hurt) day when he saw Google Maps Car for the first time :)
Google Street View Driver
Google car hangout
Four google cars and the obelisco
Google car caught by another Google car
Google car crew
