NTP is great. My notebook has sub-second errors thanks to NTP.
I recently discovered it's possible to push my notebook time down to my palm pilot, so at each sync the pilot will get the correct time. Very nice. I haven't yet done it, but it clearly belongs.
On my new Nokia phone (3315), I saw one feature "time sync if operator supports it" (for the first time). I have "yes" with much joy. I just checked, and the error between the notebook and the cellphone was around 1 second. That must be the computer at the GSM vendor (Airtel) not having Unix and NTP? It sure sounds like an obvious thing that ought to have been in GSM all along.
My wrist watch is still a mess. I occasionally sit and get the error between the watch and the notebook down to less than a second. But it's a pain.
I often think it'd be kinda cool if there was a 1 m^3 wireless network surrounding me, so that all my devices could speak NTP to my notebook. There may be other interesting possibilities also, by having a wristwatch talk to other devices. E.g. the wristwatch could a place to do at(1) and cron(8) things which affect all devices. (I'm not sure this makes sense, maybe the UI at the pilot is much better equipped for doing these things). Well, at the very least, it'd be neat to have a watch that's always correct.
A simple and pretty solution to the time synchronisation problem is to have public infrastructure which broadcasts the time. A simple radio broadcast type of single-packet beeps, without any IP sender or recipient address, just carrying the current time, maybe with some sort of digital signature, transmitted by short-range (< 10metres) transmitters in the UHF or VHF range, would be adequate. All time-beep aware devices could receive the beeps and resync themselves.
Back up to These are a few of my favourite toys (my devices page)
Ajay Shah
ajayshah at mayin dot org