The best comedy on TV with the worst taste is It’s Always Sunny in Philidelphia.  I just finished watching the third season and found it just as hilarious as the first two.

I think Wikipedia describes it best:

The show is about four friends in their late 20s who run an unsuccessful Irish bar, “Paddy’s Pub,” in South Philadelphia. The series deals with a variety of controversial topics, including abortion, gun control, physical disabilities, racism, sexism, religion, the Israeli/Palestinian situation, terrorism, transsexuality, slavery, incest, sexual harassment in education, the homeless, statutory rape, drug addiction, pedophilia, child abuse, mental illness, gay rights, prostitution and Nazis.

And I just read that Fox has already signed them for another 39 episodes which means at least a season 6.

Until the new episodes air enjoy this promo music video for the show.