What the...?

Lots of kitchen scraps go in my compost bin: vegetable peels, seeds, apple cores, etc.  Early this spring, I turned the piles to help aid the breakdown of all that organic matter.  Despite my best efforts, something in the compost bin didn't decompose; instead, it's growing!

I really don't know what this plant is, just that it's growing noticeably bigger with each passing day. Already it has filled up the middle compost bin and is spilling over into the adjacent bins.  Seriously, this thing is growing 10x faster than anything else in my garden.  A testament to the power of compost, perhaps?

Based on the vining, leaves and blossoms, I'm guessing this is some sort of cucumber or squash.  Already a little something is growing. 

This mystery vegetable is really quite exciting. I just hope it isn't some sort of cannibalistic alien a la Little Shop of Horrors.  If it says to me "Feed me, Amanda!" then I'll know we have a problem. 

Just don't blame it on the compost.