Passengers enjoy browsing the Internet and using social networking applications while commuting throughout the city. Nevertheless, it is not always possible to access the Internet at will. First, cellular coverage can be poor or nonexistent in some areas. Second, cellular communications may be expensive for a significant share of the population. Finding ways to offload part of the cellular traffic is desirable. In this paper, we examine the possibility of creating delay-tolerant vehicular networks in the city of Rio de Janeiro, Brazil. To this end, we rely on a large mobility dataset reporting GPS positions of 12,456 buses and 5,833 taxis during a 24-hours period. We assess the data transmission viability between vehicles and show that it is feasible to transport more than 25 TB of data in a day using only vehicles, strategically placed access points, and cheap flash drives.