The classic 1985 version is my all time favorite G.I. Joe figure.  Second in line would be Storm Shadow.  I'm not sure how to pull that one off yet, but only time will tell.  Snake Eyes is another one of my very early custom figures.  My sculpting skills weren't where I wanted it to be (it still is not, but I'm learning) so the mask didn't look too good.

The mask is sculpted out of Sculpey with elastic added to hold it in place.  Face mask is typical Dragon stuff.  The bodysuit is from BBI's diver figure.  Weapon's harness and arm bands are sewn with pleather.  Katana is a repaint from Max Steel.  The base body is a BBI G3.  I'll leave it to your imagination to see what Snake Eyes really looks like underneath that trademarked mask.