Yeah, that's right- a real mecha. A company called Neogentronyx is actually building a working mecha. The details can be found at their website where I recommend you download the video of a guy explaining the concept and a little technical information (about halfway down the front page).
This is pretty cool and has some possible future military applications. Giant robots armed with MGs and RPGs have got to offer some sort of strategic advantage. If the US Army likes their shiny plastic rifles so much, I wonder how they'll feel about this?