Parking Panda, Baltimore

Parking Panda describes itself as "a community marketplace for parking," one that benefits both those seeking spots and those with spots to fill. Commuters in more than 40 major cities can either go online or use the mobile app to search an area and time of arrival, which will turn up a map with pinpoints of available spots. You can reserve and pay for the spot electronically, and even view a picture of the space you've selected to be sure it is in fact on planet Earth. Many locations are automated, allowing you to enter and exit the garage directly from your smartphone, just look for the "PandaScan" locations.

Garage and lot owners can list their space online, specifying the rate and time of availability. Operators will be paid instantly upon reservation, ensuring they won't have to track down parkers by the scent of their tire tracks.