Ichiban Ushiro no Daimaou - Mindless fun and GAR in an explosion of fire and pew pew lasers that never stopped being both ridiculous and fun to watch from start to finish

Durarara!! - I felt the second part wasn't as good as the first but overall it was still a great series in all fronts that managed to deliver an healthy dose of entertainment with each episode

Angel Beats - I won't compliment the plot too much as it got somewhat clusterfucky towards the end but the characters were likable, the animation was great and the soundtrack was amazing Also there was tenshi, she alone takes the anime to the top

Honorable mentions:

B Gata H Kei - I expected nothing out of it and found the first episode quite boring but my persistence paid off in the end, the perversion of the main character won me over eventually