A method of coordinating vehicular traffic proximate to an intersection, a controlled-access roadway entrance, controlled-access exit ramps, or merging traffic lanes, comprising: communicating with at least one dynamic traffic control system located on-board a vehicle proximate to the intersection, the controlled-access roadway entrance, the controlled-access exit ramps, or the merging traffic lanes, so as to establish a dynamic traffic control plan for avoiding a travel-priority conflict in the intersection, the controlled-access roadway entrance, the controlled-access exit ramps, or the merging traffic lanes, where establishing the dynamic traffic control plan includes using a travel-route database to inform the dynamic traffic control plan as to route-specific conditions, the at least one dynamic traffic control system is communicating in an ad-hoc vehicle-based network to collect data and/or inputs relevant for the travel-priority conflict on which the dynamic traffic control plan is based; coordinating with the at least one dynamic traffic control system via said communicating to elect, based on any one or more of the ability to stop safely, the traffic density on various approaches, and being closest to the intersection, the controlled-access roadway entrance, the controlled-access exit ramps, or the merging traffic lanes and from among candidates consisting of the vehicles being part of the ad-hoc vehicle-based network, a dynamic traffic controller as a temporary coordinator vehicle responsible for temporarily coordinating the dynamic traffic control plan and communicating an instruction from the dynamic traffic control plan to other vehicles in the ad-hoc network; presenting in the other vehicles the instruction to an operator by means of displaying one or more of the following: a virtual traffic signal; a virtual traffic light; and a travel-directional indicator. communicating with at least one dynamic traffic control system located on-board a vehicle proximate to the intersection, the controlled-access roadway entrance, the controlled-access exit ramps, or the merging traffic lanes, so as to establish a dynamic traffic control plan for avoiding a travel-priority conflict in the intersection, the controlled-access roadway entrance, the controlled-access exit ramps, or the merging traffic lanes, where establishing the dynamic traffic control plan includes using a travel-route database to inform the dynamic traffic control plan as to route-specific conditions, the at least one dynamic traffic control system is communicating in an ad-hoc vehicle-based network to collect data and/or inputs relevant for the travel-priority conflict on which the dynamic traffic control plan is based; coordinating with the at least one dynamic traffic control system via said communicating to elect, based on any one or more of the ability to stop safely, the traffic density on various approaches, and being closest to the intersection, the controlled-access roadway entrance, the controlled-access exit ramps, or the merging traffic lanes and from among candidates consisting of the vehicles being part of the ad-hoc vehicle-based network, a dynamic traffic controller as a temporary coordinator vehicle responsible for temporarily coordinating the dynamic traffic control plan and communicating an instruction from the dynamic traffic control plan to other vehicles in the ad-hoc network; presenting in the other vehicles the instruction to an operator by means of displaying one or more of the following: a virtual traffic signal; a virtual traffic light; and a travel-directional indicator. a virtual traffic signal; a virtual traffic light; and a travel-directional indicator.