I have always been surprised by the high price of GPS modules that provide a location and a time reference.  There is a module developer seeking funding on Indiegogo for a sub $15 module that has a modern GPS receiver and CPU on a tiny PCB.  For details see this link http://www.indiegogo.com/projects/navspark-packing-32bit-features-and-gps-into-8bit-size-and-price/x/5740438

I would like to see this project succeed so please tell your 5000 closest friends about it.