[BFay]

I also enter an absurdly old date, and usually I'll try setting an impossible day/month combo like February 31st... sometimes it actually works!

[thescriptkiddie]

I always go for January 1st, 1970. It is (nearly) always accepted on the form because it is a perfectly valid date to be born, but I like to imagine that some analyst is pulling their hair out thinking they have a null coalescing bug.

[function_seven]

My favorite irritating date is "1969-12-31" because now I know I have 2 problems: the coalescing bug and a timezone issue. :)

[Tepix]

1970-01-01 is the way to go! The more, the merrier...

[evanb]

In Sweden in 1712 there was a February 30th. But never a 31st.

https://en.wikipedia.org/wiki/List_of_non-standard_dates