This might be better suited to the cukoos nest but feel free to move it.
Basically one poster makes a wish, the following poster grants it...but with a stipulation

i.e.:
Deadwing: I wish i had a million quid
next poster: granted. However the feds bust you for not paying tax on your million and you wind up in the joy with a big black cellmate called bubba who cant keep his eyes off your ass
I wish i had...
etc etc.
Ill start the ball rolling...
I wish i had a kickass job