Use this to convert a texual date / time representation into a unix timestamp.
An interesting side effect, you can also use this form to tell you the day of the week, of dates in history, or dates in the future.
This tool uses PHP's strtotime( ) function.
Some of the formats you can use:
1972-09-24# ISO 8601
72-9-24# Assume 19xx for 69 through 99, 20xx for 00 through 68