Note: this writeup only describes the skilling in a Norwegian context.
Skilling was a monetary unit in Norway from 1816 to 1875.
Two years after Norway's separation from Denmark and the union with Sweden, the Norwegian parliament Stortinget established the Bank of Norway; Norges Bank. The monetary unit was to be speciedaler (also called rixdollar or simply daler), which consisted of 120 skilling or five ort (sometimes called rigsort) of 24 skilling each.
The bank initially tried raising a fund of two million speciedaler by way of voluntary subscription, but this scheme ultimately proved itself a fiasco. Instead they invented what became known as the "silver tax". The silver tax was a compulsory contribution of silver or other precious metals, whereafter contributors got share certificates in return.
The value of one speciedaler was originally tied to the value of "one Cologne mark of fine silver" (233.85 grams), something which lasted in various forms up until 1842 when the speciedaler was tied to silver at par.
In 1874 the krone and øre monetary units were introduced and used in parallel with daler and skilling. One skilling equaled four kroner and was from then on tied to the value of gold.
The monetary units skilling, ort and daler was discontinued in April 1875, replaced by the current kroner and øre. This was done to prepare Norway for the Scandinavian Mint Union in which Norway, Sweden and Denmark were to introduce a common coin based on the value of gold. The idea behind the union was that money from all three nations would be legal tender throughout the mint union. The union was established in October 1875 and lasted for all practical purposes until 1914. It was formally abolished in 1972.
The term skilling is somewhat commonly used in Norway today, mostly in proverbs and as slang for money. Å snu på skillingen means spending your money wisely to make them last longer.
Source: Norges Bank's web page "Glimt fra historien" <http://www.norges-bank.no/om_nb/historikk.html>