http://www.analogman.com/singblues.htm
You CAN sing the blues if:
a. you're older than dirt
b. you're blind
c. you shot a man in Memphis
d. you can't be satisfied
But not if:
a. you have all your teeth
b. you were once blind but now can see
c. the man in Memphis lived.
d. you have a retirement plan or trust fund.