So my better half sends me 4 text messages from Melbourne today, then gets on a plane, (admittedly, Jetstar

), and flies to Hobart. That's followed by a 40km trip home.
After making a cuppa, I get 4 text messages in 3 seconds (4 experimental trials). Given a travel distance of 758km and a travel time of abt 90 minutes, I calculate the correct speed of light as 140 mps! (Telstra time!)