The Far Side, a single-panel cartoon by Gary Larson, obviously went too far to the side some time ago and threw great chunks of the populace into paralytic confusion.
— Newspaper Columnist, Chicago
Anyone familiar with Gary Larson's The Far Side knows that absurd, surreal humor is one of his hallmarks. Cows are another. Frequently, he draws absurd, surreal cow cartoons. They're not supposed to make sense, that's part of the joke.
Until Cow Tools. Cow Tools was an absurd, surreal cow cartoon, like many others Larson has drawn. Except this one was slightly different. In what can only be described as a lapse of judgement, Larson accidentally drew a cartoon that almost made sense. Almost being the operative word.
Cow Tools featured a solemn-looking cow standing on two legs, near a barn, with a table in front of her. On the table lie several crude-looking tools. According to The Prehistory of the Far Side, none of these tools were supposed to be functional or even identifiable in any way. They were supposed to represent a further step down from stone-aged implements, in that they were supposed to look not only crude and primitive, but more so than even man's crude and primitive ancestors would have made. Larson's error in judgement was making one of the tools resemble a rough-hewn handsaw.
Fans were perplexed. Had none of the tools been identifiable, we would have chuckled and moved on. But that thing on the right, it's a saw! That's a clue! The joke must lie in identifying the other tools! That one there, if you squint just right, is it a hoe? And the one in the back that looks like roast duck, is it a hammer? What's funny about a hammer?
The newspapers syndicating The Far Side were inundated with letters begging for an explanation, one that could not be provided because there was nothing to explain. Overnight Cow Tools became one of Larson's most infamous cartoons (other notable mentions include "Tethercat" featuring two dogs playing tetherball with a cat and "When car chasers dream" featuring a dreaming dog howling atop a car which he had just caught, which unfortunately, due to an awkwardly placed transmission case, looked like the dog was having sex with the car). Larson eventually had to write a press release explaining that there was nothing to get, it was just an absurd, surreal cartoon of a cow with primitive tools.
In Larson's words, "So, in summary, I drew a really weird, obtuse cartoon that no one understood and wasn't funny and therefore I went on to even greater success and recognition. Yeah — I like this country."
Swap reports that a Linux utility called Cowdancer is another kind of cow tool. Cowdancer builds an OS-inside-an-OS where you can build Debian packages. It's used for getting the least number of Debian packages required for building a package and making sure the package builds correctly inside this simulated Debian tree. Cowshell and Cowbuilder are utilities inside the Cowdancer package. Debian has other cow jokes here and there, like apt-get moo.