.... I'd rather pull over and text them myself, or maybe even use my Bluetooth to get the device to type and send it for me, at no point do either of these options cost me a $100 (unless trying to text the message whilst driving and get caught by the fuzz, then it's cost efficient to buy).

"Hello, I appear to be running late for our appointment, my last verified location was The Rat and Cabage Ale House. Calculations based on historic data and projections relating to my current position estimate I should be with you by 3:17 AM Sunday Morning, please accept my appologies for not being arsed enough to call you in person"

If your tight on money and have a secretary then CoPilot Live can do much the same thing for free. I have web n walk, HTC with copilot and once I set up real time tracking, anyone can track my location via a web browser. Works quite well

So in theory, if the ETA is beyond that of the meeting time your secretary can call in to let them know.

Now, all I need is a secretary!!

I think I'd rather just be polite and call myself, or make the effort, and arrive on time