nothing goes past the "tin soldier" or the "bush billy"
just get an ordinary can (drink the contents first preferably) then make a "bowl" by denting the can on one side, using a knife, or pin or ive even used a rock before, make a few small holes in the bottom of the "bowl"
load up your green, and toke it through the mouthpiece of the can... is really harsh, isnt very efficient but used to do it all the time while "guerilla" smoking back in my younger days, and it gets the job done