Thanks for the dialog thus far everyone. I am not trying to synchronize nuclear launch codes here - if they stay within 30 seconds of each other I will be happy. Well, honestly that is reason number 1; reason number 2 is most of the clocks examples online are pretty much baked and ready to go. I wanted to add a little 'something'.
The wireless is very appealing, as the clocks could be in different rooms etc. Xbee seems to be a bit overkill for the job. Would something cheaper such as these wireless modules do the trick?http://www.glacialwanderer.com/hobbyrobotics/?p=291
I don't see any need for them to be speedy. I like Jacks idea of the master with the NPT server access, and it could transmit a clock signal, and everyone else could just recieve.
To that point isn't there a super low frequency clock signal generated in the US that you can receive? Any insight what it would take to do that? Thanks, and I am enjoying the dialog.