What sorts of things do you/can you feed besides silversides, worms, tilapia, trout, salmon, and pinkies?

I've seen a couple threads mentioning meat- what kinds, organs, muscle meat?

Is there anything you can buy from bait shops that might be a good treat? Leeches seem to pop up a bit in lists of garters' natural diets. Has anyone tried using them? Share your sources if you know of a reasonable place to buy things from online!

I'm aware it's not good to offer things you've gone out and caught due to parasites and toxins in the environment.

What about something like this: Can O Snails - 1.7 oz. | ThatPetPlace.com