Sadie and Ginny's breeder has bunnies and whenever we're visiting, Sadie has her nose right up to the cage. She'll occasionally bark at them and get excited when they move, but I firmly believe that she'd never try to kill one if given the opportunity. She just wants to play. The same goes with Ginny.
I used to have a cockatiel that LOVED to tease Sadie when I had him out. A couple of times he'd fly and land on the ground, and Sadie tried to pick him up. Each time she was extremely gentle with him. We got to Sadie before she succeeded in carrying him, but we were never really worried. It was VERY funny, as Rocky was always highly insulted by the act, but never really stressed.
Sadie and Ginny both bark and carry on when they see squirrels and cats on walks, when in actuality both are great with cats. A friend of mine has a kitty that plays with Ginny. Ginny also has another unusual friend, a pot bellied pig named Lily that she loves to play chase with.
Lily and Ginny (I'm not sure if this link will work)
http://www.facebook.com/#!/video/video.php?v=10150340108050594&subj=518036434
Toby I'm not 100% sure of yet. From what I've seen, he has a healthy respect for cats. I don't know if he ever had a bad experience, or if he'd just never seen one before, but he made sure to stay FAR away from them I imagine he'd be the same around other small animals.