And what would it's biggest weakness be?

Teleportation. (Yeah! Sell em' your backpack)

I fucking love teleporting. I just, really fucking do. It's got so many practical applications, and no-one ever seems to exploit it.

Only major weakness I can think of comes from Skulduggery Pleasant, where teleporters are uncommon, but known, and one is easily assassinated because in combat, it's known that a teleporter's first move is to blink behind the opponent. Guy ends up with a sword in the gullet.

Hmm. Toss up between flight and shapeshifting.

Flight is a recurring feature of dreams for me and often works in similar ways, usually limited to only a couple of stories high tho'. [I dunno what sort of weaknesses that power might carry though...in some cases when I've dreamt about it there's...not really any traction in mid air, naturally, so changing direction abruptly is kind of difficult, so maybe that.]

Shapeshifting is just a comfort thing for me more or less, wouldn't really matter to me if people knew I was or not. Lots of practical things that can be done with it though, for sure.

Luck.

Basically, probabilities would shift in the favor of my desired outcome around me, in a big way. I could reliably make a living at the casino, in a fight my opponents are more likely to make a blunder, I get the big loot in MMOs more often than others...

The weakness would be that knowing my temperament I could get overconfident and bite more than I could chew even with my luck.

Shapeshifting. I would go by the superhero name Miss Nobody :)

I would have the ability to control smoke, similar to how benders control their elements in Avatar. I've always thought it was an inventive power that could be used in different ways.

It's main weakness would be any strong wind. A good gust of wind and all the smoke just blows away...

I cannot believe no one came up with the obvious yet: Mind Control.

Weakness? A superpower makes you inherently superior to your normal self. Of course someone could most likely still kill you in combat, even a Mind Controller still is mortal. I do not see the need to get into combat in the first place though.

Reality Maniupulation

Well see, that's my IDEAL choice, but for fairness sake, teleports.

The concept is that with Reality Manipulation you have ALL th super powers :3

What would the weakness be?

Power corrupts. Absolute power corrupts absolutely.

You have the power to do anything... Do you think you could remain sane with your mind?

Also, I'd take immortality. Because who doesn't want to live forever, aside from the droves of people who've tried to convince me that I don't want to live forever.

The power to stop time, for any duration, and without aging during stopped time. Time can remain frozen even when I sleep (because I know I'd be using it for mid-day naps), but it resumes if I happen to die, in order to avoid any nightmarish implications stemming from hypothetical accidents.

Weakness is it has a cooldown period equal to the previous stop's duration.