It is of course a leap year this year, which means we get a February 29th! I’ve a friend who was born on February 29th; they’ve only had 4 birthdays!
In the UK, February 29th is the one day that a woman is allowed to propose to a man. This goes back to when English law did not recognise February 29th as a day, and given that it had no legal status, tradition can be broken with on this day.
February 29th, 1504 was successful for Christopher Columbus. His crew was marooned on Jamaica, without food and facing starvation. He found out that a lunar eclipse was due and so told the local chiefs that if they did not provide him with food, God would darken the moon. The lunar eclipse began as expected and the chiefs, beginning to panic, provided him with food.
Historic UK has some more info on the traditions and superstitions behind February 29th.