9. Use your smartphone without a connection
If you cross international borders, but don't want to shell out $5 million/minute for data and voice, and don't know how to get a local SIM card, then you effectively turn your phone into an expensive brick.
Well, it still has its uses, even without a WiFi connection. Save local maps for offline viewing (here’s how to do it), then put your phone on airplane mode; since the GPS is separate from your phone's Internet connection, you'll be navigating like Magellan (or DeSoto) in no time.
Plus, the battery'll last longer if the phone's not continually searching for a signal, and it can still connect to WiFi when available.
Now you just have to worry about someone stealing the damn thing.