There are obviously SO many. However, I, like Warlord, tend to favor the not so in-your-face slap stick humor. Don't get me wrong, I get it, and I enjoy it, but I tend to get so much more 'mileage', humor-wise, out of the darker, not so obvious stuff.
While Slingblade was one of the most melancholy movies I have ever scene, so much so that I only watched it all the way through once (MAYBE twice), however, Dwight Yoakam's Doyle Harsgrove character is hilarious, steals the show, and is the reason that I have watched every scene he is in thousands of times.
All time classic...http://www.youtube.com/watch?v=Kurfhh40PLY