My all time favorite skits from Mad TV are the Stuart ones. Here are some of the best.
http://www.youtube.com/watch?v=EyDbK1PZFhg
http://www.youtube.com/watch?v=x307ddnu50Y
http://www.youtube.com/watch?v=WyTnH26ppQw
http://www.youtube.com/watch?v=if2gc-ntqA0