#5: (Tie) Kádas Opening / Ware Opening
#4: Polish Opening
#3: Bird's Opening
#2: Barnes Opening
#1: Grob Opening
This actually exists...
Other candidates are the wayward queen attack, bongcloud, ross gambit, duras gambit
KieferSmith, bongcloud is good !
THE WORSTFISH GAMBIT!
nimzowitsch!