2digit.org

The "27 Club": A group of famous musicians who died at 27 for various reasons, leading to a superstition that it's a particularly dangerous age.

Early 20th century American fad expression meaning to make a hasty departure

I Can't Drive 55, Sammy Hagar's classic hard rock song (with a very popular music video) about tyrranical speed limits.

Jesus' age when he died. (Some disagreement about this.)

Herbie the Love Bug (I'm not old enough to know what this really is)

In Back to the Future, the Delorean time machine can only time-travel after it hits 88 miles per hour.

">"> Not sure who made this, but thanks for revealing a bug in my parser!

When something is 86-ed, it's canceled. "The term eighty-six was initially used in restaurants and bars according to most late twentieth-century American slang dictionaries. It is often used in food and drink services to indicate that an item is no longer available or that a customer should be ejected."

Hexadecimal, or base 16, used to represent binary data in a semi-human-readable format.

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

The infamous "Hitler Number". 88 is used as a neo-Nazi code to mean "Heil Hitler". H is the 8th letter of the alphabet, so 88 = HH.

2⁴ (or 2²²)

"The Eleventh Hour": an expression meaning "at the last possible moment". It comes from a passage in the bible which is famously difficult to interpret.

The number of jurors on a jury, as seen here in 12 Angry Men.

Dalmatians User was banned for this post. ...jk but fr wtf does this mean

Again with the Swedes and their weird numbers (see 17). During World War II, sjuttiosju (77) was used as a password at the Swedish border, since it's difficult to pronounce if you're not a native speaker. (The SJ sound has no equivalent in English or almost any other language, and it's used twice in quick succession here.)

Catch 22 - This comes from the novel of the same name written by Joseph Heller in 1961 and is a paradoxical situation which you cannot escape due to contradictory rules.