It is said that laughter has existed since the dawn of mankind. Cavemen laughed to signal to the rest of the group that the danger had passed. Nowadays we laugh at everything from someone losing his pants to something terrible happening. It's about the brain not knowing how to react and then we laugh. It seems that we find different things to be funny but it’s pretty common to laugh if someone else starts laughing. Once we’ve started laughing the body releases endorphins and they make us feel good. Nature has provided us with laughter in order to absorb all the atrocities that we are exposed to. Otherwise, you’d probably self-implode every time the bus was late or someone was mean to you at work. Then the world would have been quite empty of people and instead there’d be small piles of clothes here and there to remind us of the annoying situations that had arisen. Not so nice.
You can either visit an authorized laughter therapist or you can self-educate yourself in laughter therapy. There are CDs and books that in a pedagogical manner give examples of exercises in laughter therapy.
Bonus: http://www.skrattaforlivet.se/
Bonus 2: Laughter is contagious http://www.youtube.com/watch?v=kQFpOiX515w
Required time:
1 hour or less
Cons:
You can get cramps in the jaw or a stomach ache if you laugh too much. How to stop laughing can sometimes be like trying to suddenly stop running downhill.
Pros:
You release endorphins and you can infect others with laughter, which in turn allows them to release endorphins in their bodies. A positive energy that spreads like ripples on water.