Have you ever think about this before,being able to walk while you are physically dematerialized?.. Suppose that you were given the disappearing formula that works only for three hours of being totally invisible to others, while no one can see/feel your existence! and the chance of having this powerful formula are given for only once. Now that you have the only one chance to disappear physically, what would you do during your disappearance? Remember you have 3 hours only.