[grammaton]

For a good overview:

http://groups.csail.mit.edu/mac/users/rauch/worktime/hours_w...

Which is a summary of

http://books.google.com/books?id=E1clEkV_1w8C

for a more thorough treatment:

http://books.google.es/books?id=APYDRo_ATicC

Or

"Man's Rise to Civilization As Shown by the Indians of North America from Primeval Times to the Coming of the Industrial State"

Or

(and I do not intend this as sarcasm, please understand) just about any introductory anthropology textbook.

Also - and I truly wish I could find the link, but it's buried somewhere in my delicious account - there is an excellent article out there about how workers in agrarian France basically screwed off for six months at a time once the growing season was over and winter came around - the literally spent most of their time just sleeping!