The "Krampuslauf" is a 500 year old alpine (predominantly Austrian) tradition that developed from heathen traditions left over after the arrival of christianity. Santa Klaus himself is, in fact, an amalgamation of many heathen figures celebrated at this time of year. The most influencial is supposed to be the Norse god Thor, who had a Santa-esque long white beard and rode the skies in a flying chariot. The enemy of Thor was Loki, a god of mischief and evil, depicted with long horns. Whilst Thor himself was easily transformed into Santa by the Christians, Loki, being evil was not. But traditions die hard and predominantly in Austria the figure of Krampus emerged from Loki as a "Companion of St. Nicholaus".
There are two interpretations of Krampus, one simply being the antithesis of Santa Klaus. On the 5th of December, the eve of the feast day of St. Nick, Austrians celebrate Krampus by running across the city in grotesque masks and generally scaring children. This is an extension of when St. Nick makes his rounds on the 6th of December rewarding all the good little children, a task which is made easy since Krampus has been out the night before, punishing pretty much the same children with a good switching.
In other variations of the theme, Krampus is considered one of Santa's minions who follows him around and obediently hands out either presents or switches, depending on whether the child in question has been good or bad.
A more mystcial approach is that people dress up in Krampus costumes and masks to scare off evil spirits, pretty much along the lines of Hollowe'en.
To round off this fantastic tradition, after the kids have had their fun, the adults get blindingly drunk. This sounds like an excellent Toytown tradition!
