Edward Abbey's Black Sun: his novel-in-a-month.

Writer's Bill of Rights includes the rights to:
Begin without a plot. Begin without characters.
Not finish. Not defend your tastes.

See also the pages on the project to write a 50,000-word novel in November - National Novel Writing Month:

10 steps to prepare for writing a NaNoWriMo novel.
Background.
NaNoWriMo 2005 lessons learned.
Plan A.
Status day-by-day.
Weekly tips and exercises from Baty's book.
Working Days by John Steinbeck.
Edward Abbey's Black Sun: his novel-in-a-month.
Edward Abbey's The Monkey Wrench Gang: his 1975 novel.
Other writing work rates.

NaNoWriMo and Black Sun

Edward Abbey wrote the 41,158-word Black Sun in four weeks, in the evenings after working through the day.
Thus, though he did not know it, Abbey was a virtual NaNoWriMo winner!
Although his book is short of the 50K-word goal, hey, he got it published!

Introduction to Black Sun

The richness of descriptions of nature and of vocabulary ("trailing virgas, curtains of rain which evaporate midway between heaven and earth") and quotations from literature provide the usual mind-tickling with which Abbey nourishes us.

In his own introduction, Abbey writes:

"If it [this book] is at all successful then the reader will experience an analogous pleasure to that which I felt in the writing of it. And is this not the essential function of the art, to add something if possible to the sum total of pleasure and form in a world where so much is subtracted by pain, confusion, and fear."

The plot of Black Sun

The protagonist, Gatlin, is a skilled and responsible forest-fire spotter at a lookout on the North Rim of the Grand Canyon. He has few friends and is relatively non-communicative with them. He no longer has a wife, but falls in love with Sandy, a woman half his age. Some Lady Chatterley-ish love scenes interleave with goatish letters from a friend of Gatlin.

Sandy takes some solo time in the Canyon to think about whether she wants the relationship with Gatlin. Then she disappears. Although Sandy was fit and had proven able to hike solo, it is unclear whether she has died in the Canyon (as Gatlin fears) or has simply left the area to get away from his control (as I think).

As for how much is 'true' of what Abbey was like, notice the Wikipedia quotation of Stephen J. Pyne's memoir (Fire on the Rim) of fire-fighting at the North Rim. Concerning Abbey, Pyne wrote: "...fire busts came and went with hardly a word from the North Rim tower. Whether Abner [i.e. Abbey] was even in the tower, no one could say. He was a writer, and the only smokes he reported were the ones in his novels. He lived in a trailer behind the entrance cabin, but he was absent so often that he demonstrated that we did not need a lookout ... The position was abolished."

In Black Sun Abbey presents the protagonist as a responsible and competent fire watcher. Given Pyne's remarks, it is likely that the whole of Gatlin's personality is much-glorified compared with Abbey's.

Statistics of Black Sun

Some statistics (ignoring any time taken to revise and edit), many adapted from the Amazon concordance for Black Sun:

Written in 4 weeks = 28 days
145 pages: about 5 pages/day.
3 sections: 'In the forest', 'In the sun', 'In the evening'.
The sections are built of 40 short 'chapters', about 3.6 pages per chapter. Overall, the movement of the story is forward in time, but the small chapters often flash forward.
4,264 sentences (152 sentences/day)
Contains 41,158 word (1470 words/day)
9.7 words/sentence.
Readable at 5th-grade level (by Flesch-Kincaid Index).

Among the most-used words:

Word.	Occurrences in 41,158 words
again	76
down	125
eyes	80
Gatlin	179 [name of protagonist; almost 0.5%]
girl	80
go	72
good	74
know	88
love	104
man	82
now	108
old	72
Sandy	43 [name of protagonist's sweetheard; 0.1%]
see	75
time	62
water	87
yes	88