What is the best cleaning product to get permanent marker off of an iPhone case?

I just bought a case off of amazon. It's sort of a bumper like the iPhone 4 came with. Well, I was playing around with a pink sharpie and I ended up getting some on my case. I've tried bleach, peroxide, and a multipurpose cleaner. Nothing seems to work aha. I'll provide a link to the case below. I don't know if the material would make any difference for the product needed to clean it. Thanks in advance!

http://www.amazon.com/...009AY0R2I/

Rubbing alcohol is the only thing I have been able to get ink off of something, but it doesn't always work. I'm not sure it will take it off your case since you have used the other products.

I use rubbing alcohol to remove ink and permanant marker from most surfaces.

I use rubbing alcohol to clean my phones screen and housing at least once a month.