By "atomic clock" I imagine you mean the standard clock signal broadcast by the local National Standards lab - it's at Rugby in the UK, and we used clocks in the Netherlands that exploited the German equivalent.
>
> Australia doesn't seem to have one.
I use those clocks whenever possible. Only my microwave oven and my Honeywell thermostat have free-running clocks. All the others are either locked to NTP (internet tine) or to DCF-77 (the German "atomic clock" radio signal).