I used to get lots of spam. I don't any more. I don't have a facebook account, I don't use twitter. I do post to newsgroups, and use forums, and I have my own website, and my email address is on every page. I don't have spam filtering enabled on my ISP mailbox, either. Maybe because I don't give my email address to any site that requests it - if a site wants an email address to view things, I won't bother. If a site is heavy in adverts, I close it. If I'm buying something, I read the 'if you don't want to not opt-out of receiving emails from us please don't tick the box' and tick what is hopefully the right choice - or I go somewhere else if the messages annoy me. My SpamAssassin folder shows about 20 spam messages identified in the last 30 days, plus I've deleted 2 by hand. I don't reckon that's too bad.
I'm not sure what I'm doing that makes things better these days, but since those painful days of dial-up when every other message was spam, email's significantly more spam-free.