naaraya,
I have to agree with the above comments: electrical shocks are never suggested.
I would like to make 2 comments:
- instead of an electrical shock, why don't you try with a small active piezo? you will be able to feel pressure force, rather than an electrical shock... hence safer for you and the HW around you.
- you are driving a transistor, and shorting it to ground in saturation mode... never good! However, I cannot tell you how to not short it to ground, because I am afraid you would try this on your hands again...