If you are looking for something new and different to do on layovers you might want to look into geocaching. It's a hobby that's been around a long time. You use a GPS to locate an exact coordinate and once found you look around to find a hidden cache. Inside it you find a log to record your visit and usually various small trinkets. You leave one of your own and take one from the cache. There are almost 1.3 million caches hidden around the world. If you have an iphone or android there's an app for that as they say. It can be some exercise for you as well as a way to spend some time. Check Geocaching - The Official Global GPS Cache Hunt Site for more info.