There are currently none that can harm a mac.. However, if you're downloading X and you get it, there is a good chance it is a piece of malware. Even though it won't harm you, it is still there and you never get your originally intended X download. Also, I am on a Windows Network and I def. don't want to pass it off to our Windows "Friends".😛 Either way, I really just don't like Limewire and try to stay clear of it.