Charlee Bears are great! I love the egg & cheese ones. They're the perfect size.
Old Mother Hubbard, Newman's Own, Natural Balance rolls, Solid Gold jerky, Zukes, Wellness... all good brands. Some are crunchy and some are soft, so it depends on what works for you in training. Auggie is a chewer so the crunchy stuff is not from training sessions, or he'll stop and crunch away! =P I've also seen something called Arks Natural Sea something or other..? Supposed to be good for joints. Have not tried it yet, though...
Like sam, I always put several different treats into my treat bag to try and keep it interesting. =>