Okay here's an example...

Poster 1:

I wish I had some pie

Poster 2:

Granted, but the pie explodes in your face.

I wish I had new socks...

--

I'll start:

I wish I had a flat screen TV.

*Poof*

You flat screen TV is given even though it has hundreds of broken pixels.

I wish I had a carpet.

Shazam!

Your carpet appears but it bursts into flames.

I wish I had a pool.

All the water evaporated and the whole pool disintegrated into dust so you just have a big hole!

I wish I had a bigger room.

Granted, but it collapes on you.

I wish I could go to a Six Flags park. (never been there. =l )

Granted, but the roller-coasters are snakes in disguise.

I wish I had an Enzo Ferrari.

Granted, but you crashed it into a hospital and got a $1,000,000,000,000,000 fine.

I wish I had a new computer.

Granted, but your computer already has a virus that you can't remove.

I wish I had a chocolate bar.

Granted, but it's 'fun size'.

I wish I had lifetime supply of Sour Patch Kids.

Granted, but you have to pay for each one.

I wish I had my own website.