From the Community Tournament from yesterday:
"What if UT physics and such stuff would exist in real life? How'd life be like?"
Well, you'd leave your home to go to school/work and would arrive too late.
Then they'd ask you: "Why are you too late?"
and you'd probably say one of the following things:
"I was roadkilled by the bus and had to respawn at my base (aka home). Then I had to walk all the way by foot again..."
"An id10t took the Manta and instead of using it as a taxi he just hovered away!"
"I left home during Invasion time. Monster spawned in the whole town..."
"I have been killed by the bullies again. They're real team killers! They've no skill!"
"I went by Manta and met a guy with a Shock Rifle..."
"Someone spammed the way with Spider Mines..."
"I met a group of campers..."
"Someone activated the Redeemer arena mutator..."
"There were Ion Tanks everywhere... O_O"
"The server had lags..."
"EFF, YEAH!"
Then there would be BSP holes. You could see a cool HoM effect on some complex objects because of the holes. (that's something we need in real life

)
You could make a person explode by jumping 100 times on the person's head.
Another thing which would be different would be the measuring unit.
Everything would be measured in UnrealUnits (UU).
Or let's take another situation as an example: "How was your day?"
You'll most likely answer something like this:
"I woke up, jumped out of the window in the third floor to take a shortcut, lost 5hp because of the height, found and picked up a health vial, hijacked a vehicle, roadkilled 4-5 people, got out of the vehicle, had a multi kill with my Assault Rifle, died and respawned with 98 Adrenaline. I think that was all. I had a very productive day today."
So you see:
Life would be way cooler! 
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