go to ebay and type atomic clock in the search bar. Atomic clock simply means it has a radio receiver that gets the broadcasted time code off one of several radio frequencies, and decodes it. It does not actually have an atomic element for calculating time, as those are very expensive and require precision controlled temperatures and conditions.

You can find an atomic watch at sam's club. You don't have to set up the temperature sensor, and the time is pretty large,so you can ignore the other information (date, year, temp) fairly easily. Personally I find this extra information useful. Also, the one I have I bought at sharper image, but it projects the time onto a wall or ceiling, so you could just look at the projection instead of the clock.