It stared (I think) Peter Sellers as this old guy that was either the money man or the agent of "the money man" ... but he went through these various situations handing out money to make people believe or do crazy ass things...
i.e. He paid off the Oxford rowing team to fuck the race... as in, ram the opposing teams boat...
or ... there was a cruise ship that really didn't exist... it was just a set in a warehouse and everyone was convinced that the storms were so bad they couldn't go above decks...
Any recolections out there...
Edit:
The Magic Christian
(http://us.imdb.com/Title?0064622) *(thanks Cathy, et al)...
Ringo Starr plays a downtrodden homeless guy that the rich guy... um... well, buys. He adopts him and grooms him for taking over his estate when he passes... and the two of them go off to spend the bulk of his money... ("his" being the guy played by Peter Sellers). Fabo movie... :D