``Mucker'' is a word coined by the science fiction writer John Brunner in his great novel Stand on Zanzibar. The word derives from ``amok,'' which will require a bit of history. It is a Malay word, and a person who goes violently insane, rushing through the village and murderously attacking everyone in his path, is said to have ``run amok.'' In what was an egregiously idiotic statement, even for him, the eminent French critic Georges Bataille called running amok the purest manifestation of revolt, ``the movement by which man rises up against his own condition and the whole of creation.'' (Bataille never ran through the streets of Montparnasse madly slashing with a kris, so he either lacked the courage of his convicions or was a hypocrite with a small - a very small - modicum of brains.) The Malays, inevitably, were and are more sensible: they kill those who run amok.
A ``mucker,'' then, is someone who runs amok; the times havin' a-changed, now they use guns. As always, they are people driven to murderous madness by intolerable frustration, repression and conformity, whether in an isolated kampong or the Postal Service. So far muckers seem to have been mostly Americans, but just the other day the radio carried news of one in Germany.

It does Mr. Brunner's prescience great credit to have foreseen the need for this word, back in 1964; and it does the rest of us no credit at all, for letting such a word be needed.

http://masi.cscs.lsa.umich.edu/~crshalizi/muckers.html

I read this novel back when it came out, and it was dazzling. It was set in the distant future, 2010. I think its still in print, and I'll wager its still worth reading. Its one of the best works of SF predictive writing I've ever seen. Among other things, it correctly predicts computer viruses (called "worms") in the book, although it does fail to predict home computers.

The primary engine of the novel's story is overpopulation and its projected consequences,[2] and the title refers to an early twentieth-century claim that the world's population could fit onto the Isle of Wight – which has an area of 381 square kilometres (147 sq mi) – if they were all standing upright. Brunner remarked that the growing world population now required a larger island; the 3.5 billion people living in 1968 could stand together on the Isle of Man (area 572 square kilometres (221 sq mi)), while the 7 billion people who he (correctly) projected would be alive in 2010 would need to stand on Zanzibar (area 1,554 square kilometres (600 sq mi)).[4] Throughout the book, the image of the entire human race standing shoulder-to-shoulder on a small island is a metaphor for a crowded world.

http://en.wikipedia.org/wiki/Stand_on_Zanzibar

The world's population has doubled since I read this book. Nah, Thomas Malthus didn't know what he was talking about...