How do I calculate the annual interest on the funds in my savings account?

I saw on TV the other day this special about these lotto winners. One guy in particular won some ridiculous amount (like 100 million or something) and during the segment he mentioned how his money was being used. He wasn't too clear but all he said was "I haven't spent a dime of my winnings... the bank pays for everything you're seeing." Now I'm uming he put his money into his savings account and it's here that it's gain this interest. I just settled a lawsuit for a pretty hefty sum myself and want to do the same thing ... "live off of the interest only." How do I calculate how much interest a particular sum will aculate in my savings account annual? Thanks...