Download this Nixieclock [589 KB]
an you see what I mean with beautiful nixieclocks.
The neon-filled numeric displays consist of an anode, ten cathodes shaped to form of numbers. They were very popular in the 1960s and early 70s when the first logic ICs became available.
Nixie tubes were a common form of numeric display for electronic equipment from the mid-1950's thru the early 1970's, when they were supplanted by 7-segment LED displays. The basic principles behind Nixie tubes live on in applications both low tech (neon light bulbs, as are used in nightlights) and high tech (plasma display panels), but Nixies themselves have long been considered obsolete. While LEDs (and later LCD displays) are certainly superior from a technical standpoint, their aesthetics leave something to be desired. We've become used to numbers formed entirely from straight line segments, looking only vaguely like written or printed numerals. A Nixie's digits, on the other hand, are individually formed, and can easily incorporate arbitrary curves and sloped lines. The only real flaw in a Nixie display is due to the fact that the digits are stacked in front of each other, and therefore all but the frontmost digit will exhibit tiny gaps where they are shadowed by the digits in front of it.
Although the term 'Nixie' is a trademark, it has come into the English language as a generic term for cold-cathode gas-discharge numerical and symbol indicator tubes. As far as the author is aware, such tubes are no longer manufactured; but they were made in large quantities from the 1950s until the late 1970s, and are consequentially not difficult to obtain. Storage life of the tubes is virtually unlimited; and they may be expected to last for 20 - 50 years in normal use, provided that they are not operated at excessive currents and provided that all cathodes are illuminated periodically to prevent cathode poisoning.
Here is more information on those nixie tubes.