Yeah, the persona idea, in recent years, has become interesting to me, too.
For practical applications, it would allow the dom to fuck around with that persona as much as they want, without any real negative impact on the sub. I think this causes a guilt-free control, which is one of its charms.
That, and the idea of being able to change someone so drastically (or in some cases, subtly) in but the sounding of a name or small phrase gives an AWESOME feeling of complete control.
But as far as what this thread is about, there are always the classics: orgasm control, the linking of genitalia and another body part (such as the palm of the hand), acting like an animal, strip-dancing, triggered action*, mental voiding**, mild or extreme behavior modification (a sort of offshoot of triggers, really - you just change how the sub reacts to certain things), etc.
* - Trigger word/trigger situations which cause the sub to commit an out-of-the-ordinary act, either while realizing it and not having control over her body, realizing it and convincing herself that it's normal, or not realizing it at all. A classic example would be, "When I snap my fingers, you will remove one piece of clothing."
** - Odd phrasing, I know, but I don't know what else to call it. This is the process of voiding the mind of thought and emotion. It's thought control of a sort, with the ultimate goal being the sub's mind becoming COMPLETELY empty of everything except the dom's words.