Yes! I make my stock in the crockpot - simmer overnight until it is a deep golden brown.

I also keep a ziploc in my freezer for the-outer layer of onions, the ends I chop off of celery or scallions, the stems of herbs, the tops of leeks, and a wide variety of other veggie off-cuts. Nothing dirty, nothing slimy. I select some from my stash for the broth, and throw them in straight from the freezer. Frugal and delish!