Borat is a fictional character interacting with real, unsuspecting people, tho.
That's priceless.
Napoleon dynamite is along the same lines, as far as just goofy characters, not many "jokes" but ALL the characters are fictional.
Borat's only funny under the context of the situations he actuall got himself into, and knowing that the people he's ****ing with were restraining themselves because they didn't know it was a joke, and didn't want to offend this retarded foreigner. I thought the actual "plot" and scenes between him and the "director" were pointless and unfunny, but they had to add something to it to make it bearable to sit through over an hour of footage.
I mean, it was based on 3-minute segments from ali G. Much funnier in the short-chunk format, but obviously much more profitable for those involved as a movie.