2digit.org

This is the probability of an infinitely unlikely event happening at least once after an infinite number of trials. If you have an infinite-sided die, this is the chance of rolling a 1 (or any particular number) after an infinite number of rolls.

The number of squares on a standard checkerboard or chessboard.

Eiffel 65, the one-hit wonder eurodance group who gave us Blue (Da Ba Dee)

Route 66 was one of the original interstate highways, and became one of the most famous roads in America. It was removed in 1985, but parts of it still exist as "Historic Route 66."

68 is the last two-digit sequence to appear in the digits of pi, found at the 605th decimal place!

There's really nothing that notable about this number, but if you use your imagination, it kind of looks like the yin-yang symbol.