The time of day when work is over and its time to put a beer in your hand.
What time is it? I don't know but its beer:30 somewhere. (similar to margaritaville thought process)
some time after beer drinking should have started
Guy to friends: "Hey, you started without me!"
Friends: "Your bad ... it's Beer:30"
The unofficial end of the work day, 4:30 quitting time as opposed to official quit time of 5:00
I'm calling BEER:30, let's go, and it's your round as I recall
As the night goes along and the beer keeps on pouring it's only natural to lose track of time. You have to be somewhere in the morning and you're wondering what time it is. You look down at your watch and see Beer:30!!! Another round!!!
Dude 1: I have work at 8 tomorrow man, what time is it??
Dude 2: It's Beer:30!!! Gimme 2 Blue Moons!