I hide anything I see on the mains that I would ban someone for in Sapphire, because I just don't like seeing that stuff - racism, sexism, homophobia, any of those bad things. I don't think lax rules should mean that people have free rein to act like pigs. I also hide spam threads. Haven't muted any users yet, and hopefully won't have to. Besides my threads, what kinds of threads do you hide?