If you have clocked the game, then GTA still always offers fun, and often destructive things to do.
I want people to post things that are either difficult to achieve, (motorcycle on a skyscraper, methane tank jump), or just really fun/funny to do, (colliding police helicopters). These can either require cheats or not.

I threw my GTA disc in a frisby style, hoping it'd return on a tall building unit complex but it never did...

Get a helicopter and bail out when you are at the maximum height.

Jumping out of a helicopter and landing on a boat.

Can also ask a question, has anyone ever actually successfully pulled off a methane tank jump?

On the statue of happiness, try and jump out and land on the cup the statue is holding, I havent's done it yet, it's bloody difficult!

Land with a helicopter, or like jump out and land in the cup?

Pushing people off the stairs in GTA4.

my GTA stunt days are over ... just doesnt appeal to me anymore.

Races on the train tracks or in the subway tunnels. Get a load of people with bikes  or cars and see how long you can survive, great fun, especially in the tunnels as you need your headlights to be working!

You can always go for a classic:  Get a hooker, pay for sex, then as she is walking away, ram into her with your car and splatter her into the nearest wall.  Naturally you go and get your money back.

Try jumping out of a helicopter into a pool behind one of the houses or through the glass windows on the roof of a warehouse.

What I like doing in GTA games is having a few vehicles against each other, blow one up and watch it blow the others up. I've always liked that.

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