Boondock Saint's.
Do yourself a favor, and rent this. You will NOT be sorry. If you don't like it, I will personally come to your house, and re-imburse you the rental charge. (And I will beat the crap out of you as well, but you WILL get your money back

)
And there is a sequel for this movie coming out soon. (Both Independent's I believe.)
KeyserSoze