Yeah, it has happened to me once at work. I work for a food company so testing food out all day can lead to... well... not so friendly conditions.

One day we tasted a lot of food and my stomach was killing me. I decided it was best to leave at that time. Half way home I almost exploded. The bumps and climbing did NOTHING for me. The onlth thing that helped was to take off my coat (it was freezing out) and keep really cold which minimizes the need to explode for a short peirod of time.