Dangerous not as in viruses (I am on a mac), but I think the person I spoke to said torrents were illegal (he downloads movies) and perhaps I was wondering whether ISP's can take action on me if i am found downloading torrents.
This guy uses some 32 dollar software to download which perhaps masks IP's. He claims to be a software professional (but he's in rehab or detox for a few months, so i cant contact him).