What’s an anime opening/ending that gets stuck in your head like crazy?

Gakuen Heaven has got to be the trashiest anime I’ve ever watched, but dat intro tho.

Asa da! Kyou wa mabushi sugiru sunshine
ashiotomade odoridasu yo saa yukou

Kinou made wa yumesae mita day today
nagare dashitakara mou tomaranai ne

Chyoppiri fuan na kaze mo kumo mo zenbu sayonara BAI BAI
kokokara hajimaru uzuku karada katte
acchi mitemo kocchi muitemo tanoshimi darake

HAREBARE no aoi sora
miage aruki iza Heavenly every day
DAN DAN hazumu mune no naka
egaki dashita sou mugen no happy time
deai hajimeta kono shunkan sorezore no mirai kagayaku school boys

Ohayou! minna kyou mo genki good smile
kyousou da ne hashiri dasu yo saa yukou

Sukoshi mae wa shirazu ni ita history
katari dashita nara mou kiriganai ne

Yappari fuan na koi mo yume mo zenbu wasurete GUDDO NAITO
ashita ni natta ra tsuyoi kokoro datte
yoko o mite mo mae o mite mo egao ga aru sa

BARA BARA no aoi chizu
atsume tsunagi iza Heavenly every day
DON DON mieru mune no oku
idaki dashita sou dareka to lovely time
deaeta kiseki ano hi kara sorezore no omoi dakanaru school boys

mayoi nayami shizumu sonna toki mo
hajimete no kono KIMOCHI wasurezuni ikou yo

HAREBARE no aoi sora
miage aruki iza Heavenly every day
DAN DAN hazumu mune no naka
egaki dashita sou mugen no happy time
kyou mo hajimaru kono shunkan sorezore no ima ga kagayaku school boys