You now have the loudest voice ever recorded, so everyone around can hear your most intimate conversations! 

I wish I could make certain people disappear. 

You make certain people disappear.  Those people, now invisible, sneak into your house and destroy your stuff.

I wish Katy Perry had never become popular and that no one, including myself, had ever heard of her.

As you wished, Katy Perry has been heard of by no one—including you—as she was never born. When the bombs fell on Hiroshima and Nagasaki, the world decreed that the U.S. was too dangerous to allow continued existence. Foreign armies invaded America along both eastern and western shores, focused on destroying all persons, places, and things that even remotely resembled what it meant to be American. The population was obliterated; cities were leveled; the land was scorched from sea to shining sea. Nothing remained but those vindictive invaders, nothing was left salvageable, and and when the weary warriors returned to their homelands, America was nothing but a distant memory.

I wish there was a highway connecting Hawaii to the continental U.S.

(If you don’t know just how far that would be, feel free to google it ;) )

Note on alternate-timeline continuity: While both of Perry’s parents were born post-WWII, and her father was born in Kingston, Jamaica, her mother was born in Michigan. In other words, while dad might have still been around, mom would have perished in the anti-American fallout of the above scenario.

Bridge is subject to several car pile up crashes and is closed down, because of the hypnotizing miles of exactly the same thing with no change in a straight line for more time than typical person could mentally handle.

I wish the majority of humanity would leave earth and live in O'niel cylinder like space habitats in the near future.

The majority of humanity leaves Earth.  Jesus comes back to Earth, just like the Bible says, and finds nobody there.  All of humanity is condemned to the eternal lake of fire.

I wish I wasn't sick right now.

Anytime anyone else snaps, you're transported to the place they want to go. 

I wish sweaters didn't make us itchy. 

Sweaters no longer make you itch but they finally live up to their name and make you sweat uncontrollably instead.

I wish more adults remembered what it's like to be a kid.

You have a live-in chef.  It's the chef from classic South Park, so all he does is sing lusty R&B songs instead of actually making food.

I wish I could find a good karaoke bar closer to home.

A international chain of karaoke bars buys your house, the noise is unbearable.

I wish coffee tasted like it smells.  :)

You get your wish. Your coffee tastes amazing. Global caffeine consumption triples over night. Everyone talks twice as fast and sleeps half as much. The Brazilian rainforest is mowed down to grow more beans, accelerating the planet's demise. Eventually supply can't meet demand, and the price of coffee shoots through the roof. The homeless rate quadruples.

I wish I knew for certain if Sasquatch are real.

You find out that Sasquatch is real by going to visit your parents house and discover your mother having an affair with him

I wish i could go back to 2007

You go back to 2007, but find that the economic crisis came a year earlier and caused mass chaos throughout the world. 

I want to go to the future