Make a Wish. Have it horribly corrupted.

[Hitmonchu]

Granted, but it releases after you die.
I wish for the Dragon app.

[X-The-Final]

Granted, but then it blows up spectacularly in your face.
I wish to not have to be sleepy.

[Hitmonchu]

Granted, but then you can never get to sleep and you die.
I wish for more money

[Draghost999]

Granted.

I wish for you go understand.

[X-The-Final]

Granted, but then everyone's brains explode and you get covered in the icky brain-bits.
I wish for Kingdom Hearts III to finally be released.

[Silverwing Bloodsplash]

Granted, except that it was rushed so badly, it's worse then Sonic '06.

I wish I could fly.

[ajeeth23]

Granted, but your first flight ends up being worse than the Wright brothers'.

I wish for an iPhone 5S.

[Trekkie WhoLocked Fangirl!]

Granted, but its a plastic toy one that holds sweets

I wish for my migraines to stop

[Hitmonchu]

Granted, but then terrible earaches start.

I wish to be better at Photoshop.

[SirBlaziken]

Granted but you spend so much tine on it your social life is destroyed

I wish for a taco.

[Draghost999]

Granted. It's a poop-taco. Let's call it a tortilla-diaper. Eat up, it looks a lot like beef.

I wiiiiiiiiish for...... a Darkrai's collar.

[SirBlaziken]

Granted, but It turns into moldy cheese!

I wish that I could control time.

[TickTockTheCroc]

granted, but you been to age at an accelerated rate that cannot be altered  by time

[Hitmonchu]

I wish for you to make a wish

[SirBlaziken]

granted but the world explodes

I wish i was a blaziken