Wikipedia is full of weird little corners where someone felt some obscure thing was worth explaining at length. Take this as an example; a list of films ordered by uses of the word 'fuck'. The accompanying graph is especially informative.
This is an incomplete list, which may never be able to satisfy certain standards for completeness. Revisions and additions are welcome.This is a list of films arranged in order in which the word fuck is used.
Please note: The Devil's Rejects only has 203 "fucks" or derivatives according to IMDB (link - http://imdb.com/title/tt0395584/trivia)

Top 5 are ..

Rank/Movie/Year/Fucks/Minutes/Fucks per minute
1 The Devil's Rejects (2005) 560/109/5.13
2 Nil by Mouth (1997) 470/128/3.67
3 Casino (1995) 422/178/2.37
4 Martin Lawrence Live (2002) 347/113/3.07
5 Another Day in Paradise (1998/327/101/3.24

Not seen any of these but ones I have come in as follows ...

Rank/Movie/Year/Fucks/Minutes/Fucks per minute
7 Twin Town (1997) 320/99/3.23
10 Born on the 4th of July (1989) 289/145/1.99
15 Pulp Fiction (1994) 271/154/1.76
17 Reservoir Dogs (1992) 252/99/2.55
21 Goodfellas (1990) 246/145/1.70
26 True Romance (1993) 225/120/1.88
28 Scarface (1983) 218/170/1.28
29 Training Day (2001) 211/120/1.76
65 Lock,Stock & 2 Barrels (1998) 114/105/1.08
68 Point Break (1991) 105/120/0.88
69 Trainspotting (1996) 104/94/1.11 (suprised this is so low)


more here ...