Things to do in GTAIV when you're bored..

1) Go to Cluckin' Bell.
2) Get a Police Cruiser.
3) Get at least 4-wanted stars.
4) Act (shoot, drive, etc.) like in movies, for example, Die Hard 4.
5) Wait when The Lost And Damned comes out for PC and PS3.
 
I drive a Comet or a Turismo around the docks and its super funny when you hit a tire and flip in to the water :P
 
Get in the Patriot drive at ridiculous speeds and try to t-bone a car and watch it go flying and in some cases have the car explode for no reason.(Rammed a police car than it suddenly exploded when i hit it then my car exploded.)
 
Ride a motorbike down the sidewalks in Star Junction.

Figure out what side Niko gets out of.

Drive really fast.

Hop out right in front of pedestrian.

Body slam someone at 100 mph.
====================
Get bat.

Walk down a street, and hit everyone you see in the head.

Yell "REFORMATION" each time.

Have a mob behind you trying to kill you.

Watch as fights break out everywhere.

Call police.
 
See how high a number you can get on the police radio message: "Subject is doing XX (mph) ....."
Unfortunately I don't think it goes higher than 90, so getting any higher could possibly keep you occupied for a loong time ;)
 
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