Good morning (barely) and welcome to the pointy end of the Mecha countdown. Since I and most of my family were in a heat induced quasi molten state yesterday, I was super unmotivated to get this post out. Since I figured this would be trickling into July anyway, might as well just be lazy and go one more day in, right?
#2 Martian Tripod
Admit it, you didn't see this one coming, did you? Hailing from H.G. Wells' The War Of The Worlds, this is sort of the grandaddy of all mecha. I got interested in them because of the Scrin Annihilators from Command & Conquer 3, which also had three legs, shields, and lasers.
I placed it high because of how important they are to the genre, and also because of the recent rennaissance they have been experiencing in fiction and gaming due to the steampunk thing.