My sub and I have enjoyed the following:

Keep in mind, BTW, that we live in New York City area, so you can get away with quite a bit....

1) I require that she wear an impossibly short miniskirt in public, and then periodically finger her in front or back as we walk.

2) While riding in the car, I pull her panties down to around her knees and leave them there. We get some very interested looks from people passing in trucks, minvans and SUVs.

3) I require that she finger herself, or I finger her, fully exposed, as in the above.

4) I require that she have an "accident" and wet herself in public, then walk around all day in that state.

5) Wearing her little miniskirt, having her sit on a park bench with her legs spread, and sitting nearby to watch the looks that she gets while I enjoy her humiliation.

6) Keeping her collared and leashed at all times in public, and walking her that way.

7) Sitting in the park, and requiring that she sit at my feet on her knees, with her hands behind her back and head and eyes cast downward.