Bow and arrow. I am a real fan of bows. Second would be the Ocarina since i loved playing songs on it. Then the double clawshot since it was quite fun.
The sword, any and all, easily the most fun. The transformation masks in MM coming next. Boomerang was fun as well. ALso the medallions in ALTTP, the power unleashed by those things was awesome.
the bow from TP, i love how they used the eagle eye and the bow together almost like a sniper. now im not a shooter game person, but that was pretty EPIC!!
The Fire Rod from Four Swords Adventures. I love running through a frozen wasteland lighting everything on fire. I find it under appreciated and would be incredibly excited if it were put in a 3D console game.