A treasure hunt around the local area using maps to visit as many checkpoints as possible in a given time.
Local area map with various checkpoints marked on it & their points value, 1 car & driver per team, 1 smart phone with data capability per team.
Each team receives a map with the various checkpoints marked & a list of the points value for each checkpoint (higher points for further away checkpoints) We use Schools, Scout Halls & public parks as checkpoints as these all tend to have recognisable signs outside. We also include the 2 trig points in our area as compulsory checkpoints. Each team is allocated to a driver & then has to plan a route to visit as many checkpoints as possible in order to score the most points in the allotted time, with points deducted for every minute a team is late for their return. Once a team arrives at a checkpoint they take a photo of the whole team with the sign or whatever identifies the checkpoint, & then upload it to a specially created Facebook page via their smart phone. A leader back at base then monitors the Facebook page & regularly updates the scores & can also post spontaneous incentives & bonus point scenarios. When all teams return scores should already be calculated with just the deductions for late return to be considered. Award prizes for winners & maybe best photos.