I use "ok" also, although I've heard a lot of people use "free" because it isn't as common in everyday conversation.
I use "wait" frequently, such as not bolting out the door ahead of me or getting too far ahead of me when we are walking, but not heeling. It's a loose command, doesn't require precision, but gets the job done.
My boy has to dance for his dinner. I know, I know, that's mean. But he's always done a little "dinner dance" since he was a young pup and we get such a kick out of it it's become a requirement.