Trash Squash

Every year, I get a surprise from my garden.  The surprise of the year always starts growing in my compost pile.  I see it sprout and let it grow to see what it will develop into.  Last year, I had a bounty of acorn squash from my compost pile.  Here is this year's surprise.  The compost is at the very end of my garden.  You can see it growing towards me and taking over everything there as well as growing up into the lilac bush behind it.

Here's a close-up of this year's surprise squash.  I'm not sure what kind it is.  I don't recall eating anything similar to this.  Does anyone know?  Right now they are still kind of small in size - about the size of a softball.  I'm hoping they are edible and not decorative.  I don't think I had any decorative gourds given to me last year, that I can remember. But the bumpiness factor makes me wonder if it's edible. 

Here they are up in the lilac bush.  They look like little squash ornaments dangling from the branches.

So I need help from all of you squash experts out there to help me identify my mystery squash. Any ideas?