I haven't really tried too many things as far as treats. I did read on another forum of someone giving them crickets as a treat. My boyfriend tried that and they went nuts chasing and chomping them down. We haven't done it since, and not sure if they really should eat them or not. But it was interesting to see.
I might just have to try a couple of the things others have mentioned just to see how they like them. While I know they love their hog feed I'm sure it's nice to get something different every once in awhile. :)