I found this guy at the Trevi Fountain in Rome. There were about four hundred million other people there as well, so its not as though this is an exclusive however I feel it warrants a mention.
He was carrying an inkjet printer and a digital camera around his neck. Passersby could get their photo taken, downloaded and printed out for the meager sum of 5€. I think he may have needed to replace one of his ink cartridges though as the prints he was churning out were fairly faded and streaky affairs.
mobile printer guy
I am not sure how he powers the thing though as I am fairly certain that the Trevi Fountain does not have a cable tray running along its perimeter or sub-floor services for that matter.