Yeah, I know about Rugged Helmet. The thing is, instead of making thee attacker loses 1/8 of its max HP (like Rough Skin and Iron Spikes), the Helmet makes the attacker lose 1/6. That's pretty nice, if you ask me.
And I've seen the Balloon. Makes the holder immune to Ground moves until it's hit. It looks useless, but for certain Ground-weak Pokemon (like Doryuuzu), it buys a setup turn. I just wish the games didn't have that notification message.