For two or three years I was a member of a few laughter groups here in Melbourne Oz.
They say that laughter is the best medicine....well I don't know about that, but as a sufferer from depression I did find it had a helpful side.
These groups essentially create humorous situations,miming, play acting childishly etc incorporating laughter and a degree of spontanaiety and silliness. There is an anchor person, who runs the show, while individuals do a short routine; this is followed by coffee.. I found it quite fun BUT....
I was later to discover that large corporate groups ran a laughter industry, running expensive world wide workshops and even ran a laughter University providing degrees in laughter instruction. I realise business is business but the whole spirit of the thing was compromised for me.