It is true that Ghost allows you to pass through units when running around but this still does not prevent Powerball for discharging when you pass through them.

check out my new rammus video. i play him as a jungler mostly. that seems to have the most success http://www.youtube.com/watch?v=nbPja5WxvjA

This is the first guide ive commented on, because this is a great build.
I used this build for my first time rammus and i went 1v4 and they had a hard time killing me!
Thanks!

Overall it looks like a good build, however, you state that Ghost doesn't allow you to powerball through minion waves. However, ghost allows you to travel through any minions. I haven't tested it with the powerball but it seems like it would work.

I made this guide because all the high rated guides on Rammus have him building for AP or AD or just generally like a carry. This is silly. That sort of thing only works against noobs. This build is intended to be used along side a team of reasonable skill with a good carry against another team of reasonable skill. Rammus's main role is as a tank with a strong bent towards assisting initiating ganks and causing havoc with his taunt. Nuking with powerball should only ever be done for the lulz, not as a build strategy.