The comedy troupe Radio Free Vestibule used many sound clips of Laurence Olivier to make an endorsement for Diet Coke. Here's the text of it, to be read in wildly varying tones of voice with a halting cadence:
"Hello, I'm Laurence Olivier. I've been dead for over two years now. But now, through the marvelous technology of tape editing (very stilted; Laurence never said "tape" or "editing" so they had to find phonemes), I'm able to speak to you from beyond the grave. What you are listening to right now has been made by cutting together things I said in my many films and interviews. Although I never would have endorsed a product like this when I was alive, my estate has determined that if I was alive, I would really want to tell you how much I enjoy the taste of Diet Coca-Cola ("Coca-Cola" is also very stilted). I think Diet Coca-Cola is really excellent, dude. It's awesome. I wish I could have some now. But I can't, because I'm dead! But take it from me, Laurence Olivier. Maketh thy mouth alive with Diet Coca-Cola. It's everything you want it to be!"
To hear this marvel for yourself, you'll either have to buy the Radio Free Vestibule CD on which it is recorded, or snarf it off of your favorite music "sharing" network.
I've been told that this is a fake, comprised simply of troupe members doing Laurence Olivier impressions in various tones of voice and with different background noises. It's still pretty funny.