Montreal has adopted a great new bike system called Bixi, and it seems that it's catching on and will likely be expanding to more cities. One of the coolest parts is the iPhone apps available for it. Bixi has opened up the station data to allow developers to use the iPhone to get real time data for the number of bikes available and docks open at each of the 300 stations.
A cool product I'd like to see involves the city using the parking terminals, that are on every street in downtown Montreal, to start building similar apps to display available parking spots. Every time you pay for your parking you select your spot and time length, the city should establish an API for developers to access and display this information on a variety of devices.
The city could take this data and install parking availability signs on street corners, significantly reducing parking frustration and wasted time. They could also turn the evil up (and increase revenue) by increasing the meter maids efficiency with devices that only show spots that have expired.