Maria Holic! Always my first choice when someone asks for a comedy anime. Also try:
Is This A Zombie?
Air Gear (WARNING! It's really freaking stupid. Funny, but stupid.)
Welcome to the NHK! (Though that's more dark comedy.)
Sabagebu! (pictured)
Nichijou
Daily Lives of Highschool Boys
The World God Only Knows
Princess Jellyfish
Love Lab
Nisekoi
Senyuu.
Sayonara Zetsubou Sensei (Dark Humour)
My Mental Choices are Completely Interfering With my School Romantic Comedy
Ben-to
1)Noucome
2)Soredemo Sekai wa Utsukushii
3)Zero no Tsukaima
4)Seto no Hanayome
5)Tokyo Ravens
6)Bokura wa Minna Kawaisou
7)Mangaka-san to Assistant-san
8)My Romantic Teen Comedy SNAFU-Oregairu
9)Blood Lad