Though I don't do it, try one of those programs that allows you to track your friends location while on the phone with them. You'll need 4G for the GPS, but you can talk to them while you close the distance to meet them. Pick up one and go to the next. They'll be impressed.
Anyone know if you can do real-time YouTube. It would be interesting to real-time post someone's reaction to a surprise B-day or other surprise festive event and have it available to other friends who can't attend almost instantly.