When I am playing dub to my boyfriend we're content for me to be tied and bound in the usual manner. However instead of my tying him up when it is his turn to be the sub, we've found something a little more "creative." During those times he will do something he rarely does...he'll wear his glasses instead of his contacts. I have him do this because he is for all practical purposes blind without them. Once I have his glasses he's helpless. We even have a pair we use exclusively for play time that are less likely to get broken in some of our more intense times.
Sometimes I will knock them from his face or pull them off and toss them across the room. He will try to find them by feel and if he can't in a certain amount of time, he gets the riding crop. Other times I'll just grab his glasses and hide them then make him beg and do other "things" to please me in order to get them back.
I was a little reluctant at first to exploit a real weakness of his for sex games but he trusts me enough to not let his natural fear of being deprived of his glasses and contacts bother him.
Does anyone have any ideas for other things we could role play by using his glasses?