An old man lies dying in 2070 surrounded by his family. 

Trying to extract some final wisdom from him and keep him company in his final days, his son asks, "What's the part of your life that sticks out to you the most, Dad?" 

He responds, "I can perfectly remember my youth. Those summer days fifty years ago seem, in my mind, to be as clear and perfect as this moment now."

His son exclaims, "Wow, fifty years! Your memory was always so impressive, even in your old age, Pop."

"But of course," says his dad, "hindsight is 2020."

Why don't we know the weight of the rarest diamond in the world?

Never mined.

What do you call an Australian that will only eat short-grain rice?

A rice-ist.

Joey was pretty scrawny, so he had to quit his job as a personal trainer.

He gave them his too weak notice.

What do you call a depressed traffic jam?

Bummer to bummer traffic.

If Spock has Vulcan ears, what does Scotty have?

Engineers.

What you you call a day old pastry?

Yesterdanish.

You matter until you multiply yourself by the speed of light squared.

Then you energy.

What happened to the potato farmer who crossed the mob?

He's sleeping with the knishes.

Then there was the one about the brake pedal who had to leave his job.

He had to stop when he got depressed.

What do you call a chicken staring at a head of lettuce?

Chicken sees a salad.

Why did the leaders in the old Soviet Union hate riding in taxis?

The drivers were always stallin'.

How does an Australian greet his toilet?

Bidet, mate!

My wife's pretty good at making an Earl Grey.

It's her special tea.

How much food will $64 get you?

Eight square meals.