From a Greek word 'paraprosdokian'

Greek must be a very difficult language to learn because we were taught to say, 'sounds like Greek to me' for anything we did not understand. Yet, how many of us know or bother to find out what some of the wise statements we have been using are actually known as? Thanks to Bayi's pointer, we are now wiser...

A paraprosdokian (from Greek "παρα-", meaning "beyond" and "προσδοκία",meaning "expectation") is a figure of speech in which the latter part of a sentence or phrase is surprising or unexpected in a way that causes the reader or listener to reframe or reinterpret the first part. It is frequently used for humorous or dramatic effect, sometimes producing an anticlimax. For this reason, it is extremely popular among comedians and satirists.

Some paraprosdokians not only change the meaning of an early phrase, but also play on the double meaning of a particular word, creating a syllepsis.

Examples :

With a bit of sarcasm:

Hospitality: making your guests feel like they're at home, even if you wish they were.
Some cause happiness wherever they go. Others whenever they go.
There's a fine line between cuddling and holding someone down so they can't get away.
You're never too old to learn something stupid.

Some people hear voices. Some see invisible people. Others have no imagination whatsoever.

... and truism?:

Change is inevitable, except from a vending machine.
Money can't buy happiness, but it sure makes misery easier to live with.
I thought I wanted a career, turns out I just wanted pay checks.
A bank is a place that will lend you money, if you can prove that you don't need it.
A bus is a vehicle that runs twice as fast when you are after it as when you are in it.
The early bird might get the worm, but the second mouse gets the cheese.
Nostalgia isn't what it used to be.
We never really grow up, we only learn how to act in public.
To steal ideas from one person is plagiarism. To steal from many is research.
Evening news is where they begin with 'Good evening', and then proceed to tell you why it isn't.
Why does someone believe you when you say there are four billion stars, but check when you say the paint is wet?

... Clever play on words and almost like definitions:

War does not determine who is right - only who is left.
Always borrow money from a pessimist. He won't expect it back.
I used to be indecisive. Now I'm not sure.

A clear conscience is usually the sign of a bad memory.
A diplomat is someone who can tell you to go to hell in such a way that you will look forward to the trip.
A bus station is where a bus stops. A train station is where a train stops. On my desk, I have a work station.

... last but not least, a clever way of looking at things :

I asked God for a bike, but I know God doesn't work that way. So I stole a bike and asked for forgiveness.
To be sure of hitting the target, shoot first and call whatever you hit the target.
Dolphins are so smart that within a few weeks of captivity, they can train people to stand on the very edge of the pool and throw them fish.

(Some examples re-arranged, with my itchy hands on keyboard)
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