Probability of...

Probability of contracting cancer in lifetime:

Men = 44% (1/2) Female = 38% (1/3)

Interesting article about death probabilities: http://gravityandlevity.wordpress.com/2009/07/08/your-body-wasnt-built-to-last-a-lesson-from-human-mortality-rates/

Cool application to calculate death probability based on the Gompertz law of human mortality: http://forio.com/simulate/simulation/mbean/death-probability-calculator/

Probability of your house getting struck by lightning this year:

0.5% (1/200)

Probability of getting a royal flush in poker:

.000154% (1/650,000)

Probability of dying in a plane crash:

.0000111% (1/9,000,000)

Probability of having twins (or more than 2):

2% (1/50)

Probability of baby being born on due date:

less than 5% (1/20)