Does It's Always SUnny in Philadelphia count as a sit-com? I don't watch TV but happened to see it late night at a relative's house and thought it was marvelous fun.
LARRY SANDERS ! & not forgetting that work of towering genius: SON OF THE BEACH & JUST SHOOT ME it's funny, I'm in the UK & all my favorites are American
Blackadder Red Dwarf Ever Decreasing Circles The Simpsons Sorry! Fawlty Towers The Young Ones
Much the same, except you can remove Sorry! and The Young Ones, and insert Father Ted, Futurama and the three political sitcoms of Yes Minister, Yes Prime Minister and Prime Minister's Questions.
The last of these is scripted just as closely as the rest, but is often funnier.