Corrupt a wish.

Make a wish, next person grants your wish but then evily corrupts it, makes a wish etcetc.
EG
Neonk: I wish I had some cherries to eat.
Milanos: You get some cherries, but then a nearby dog woofs so hard, the cherries burst all over yo' face. I wish for a dog.
Neonk: You get a dog, but then it bites your toe off. I wish for a ...
etc.

I wish you would shutup. Yeah, you!

Granted, though someone else blabbers about.

I wish I could die.

You die but then get reincarnated as a badger. :L
I wish I could go slap Miley Cyrus in the face and become famous for it even though I don't particulary dislike her.

Granted, however, in a series of fantastic accidents, you're killed in a terrible milk-drinking accident, becoming famous as the unluckiest dead person ever.

I wish Breaking Benjamin would hurry up with their new album.

Granted, but something dramatic happens and it's never released. (:

I wish I wasn't a main target for Rick Rolling.

Granted, thought your PC becomes the target and is infected with the "Rick Roll" virus.

I wish that I was born in the USA.

Granted, your history is changed but you find yourself obsessed with the Jonas Brothers.

I wish that she didn't break it off.

Granted, thought everyone else does.

I wish school was over.

school ends only to resumes a second later due to a freak time warp.

I wish for My favorite bands to actually come to my state >C

They come to your state but then due to an alien attack in ONLY your state, they are evacuated, and you're not...so you die. hahaha. harsh. >D

I wish for a cup of tea right now. (:

Granted, but you pour it onto your *ahem*

I wish life wasn't so harsh.

Life isn't so harsh, but that's because there isn't life anymore D:

I wish there was more time in the day.

Granted, but the day never ends. D:

I wish I could visit Africa

You visit Africa, but there's nothing there at all. D:

I wish I had an easier time sleeping.