You are Immortal.

[LTlewis]

You have just discovered that you are Immortal. The simple kind, no having to repair any injuries, no aging just the best kind of immortality. What do you do first.
Myself, I go to the middle of London (my closest big city) and start to advertise the fact, jumping of buildings playing in traffic, all that stuff. Why? To see people react, do they call it a trick, am I heralded as the messiah or devil. How long before the government turns up. And if I am carted off so what. I just sit around for a century or two and then walk out of whatever ruin I?m in.

 

[Baron von Blitztank]

So what if you lose limbs? Do you just grow them back? What about decapitation? Do you grow the head back or the body?
When does the aging process stop? What happens if I go into deep water? Can I still feel pain? What happens to my blood? Does that regenerate? I wonder how long I can keep giving blood for before people freak out?

So yeah, I guess that's what I'd do. Question it a lot until I find out exactly how it works...
Then once I find out about the lack of aging I'll have to live with the depressing fact that I'll out-live my girlfriend.

 

[Keoul]

Create a costume then masquerade around as a super-powered individual for the rest of my life.
I didn't say hero or villain because it's more fun just doing whatever you feel instead of appeasing the public. And should I ever want to resume my boring life I just have to take off my mask.
Win win!

 

[MrFlibble42]

Well as my favourite Hitchhikers Guide To The Galaxy character is Wowbagger the infinitely prolonged I would have to say that if I became immortal I would spend my time visting everybody on the planet and insulting them all. In alphabetical order.

 

[Asita]

Try to figure out how I could reverse the process. I probably wouldn't reverse it immediately, but I'd want to know how to do it both to understand my own limitations and because, let's be honest, being stuck living alone after the heat death of the universe would be a fate far worse than oblivion. And given that I have no idea how hard reversing immortality would be, I'd want to get on it ASAP so I'm less likely to run out of time. ("Sorry, but the remedy requires a plant that has been extinct for the last 10,000 years!")

 

[Scarim Coral]

I will start learning new things like learning to draw or get back to 3D modellings seeing how I have all the time in the world to master it.

 

[Esotera]

I would probably start a lot of research in science and computers and try and build up a business empire. Then just help improve the earth, and colonise the stars. Then I'd probably find a way to kill myself as I don't think the human mind would function that well over hundreds of years.

 

[Professor Lupin Madblood]

Fight crime.

Honestly, what else could you do?

Start investing.

Seriously, if I'm going to be around forever I can't exactly be getting by on my current, meager salary.

Well, okay, sure, that too, but I mean really, people.

 

[Arakasi]

Start performing catching the bullet tricks where I actually catch the bullet.
I'd blow Penn and Teller out of the water.

Other than that, just live with the cash I'd make from my magic.

 

[TheIronRuler]

Kill myself in all sorts of imaginative and fun ways just so I will know how it feels and live to tell the tale.

 

[HardkorSB]

How long before the government turns up. And if I am carted off so what. I just sit around for a century or two and then walk out of whatever ruin I?m in.

What if you're caught, dissected, dismembered and each part of your body gets sent to a different facility to be carefully examined?

 

[shrekfan246]

First question: Do I still feel pain?

If not, or at least a severely reduced amount of pain, then I become Batman.

Might take a little while since I've got no money, though.

 

[GrimTuesday]

I would get into shape, because who wants to be fat for eternity?

Next I would start working on meeting powerful influential people, so that as time goes on, I can use those contacts to become a man of power and influence myself, all culminating in my rise to power. Also, I would start investing money, because while I might try it, I don't want to live on the street until the world ends.

 

[Beautiful Tragedy]

I would get into shape, because who wants to be fat for eternity?

Next I would start working on meeting powerful influential people, so that as time goes on, I can use those contacts to become a man of power and influence myself, all culminating in my rise to power. Also, I would start investing money, because while I might try it, I don't want to live on the street until the world ends.

grim pretty much nailed it, but i wouldn't want to "rise to power" i'd rather stay in the shadows and manipulate others

 

[Basement Cat]

I'm Immortal? Why thank you very much! ^_^

What would I do first? Frankly I'd relax. Seriously. I'd realize that all the problems I'm dealing with now are passing concerns and I'd truly take the long view.

I'd relax.

 

[Vegosiux]

Why, start planning world domination more seriously. And when I get there....*rubs hands with glee*

 

[Slaanesh]

Fight crime.

Honestly, what else could you do?

Commit crimes.

I'm going to jaywalk like a mother fucker.

 

[Ldude893]

Find a way to get rid of it.

Seriously, immortality is worse than death in so many levels, and any man who earns it is going to live a hellish existence. If I don't find a cure, at least find something that will bring me to a permanent coma.
Before I do all that, though, I'm going to do something worthwhile like taking up firefighting, singlehandedly bringing down North Korea, and swimming in a volcano.

 

[Brainwreck]

Get stuck.
Scream for eternity.