I'm not much of one to tell prepared jokes, but this one, sent to me by an old Navy buddy, isn't half bad. It has to do with military time, which as you may already know, is based on a 24 hour clock.
Anyway, this crusty Navy chief petty officer walks into a bar, sits at a table, and orders a shot and a beer.
The comely bar maid says, "Hey, Chief you're one hunk of a man. When's the last time you had a little action with a cute honey like me?"
The chief leans back in his seat and says "Not since 1955."
"1955?" the bar maid says. "That's a long time for a healthy guy like you to go without sex."
The chief looks at his watch and says, "You think so? It's only 2130 now."