The pop-up windows themselves have controls you can use to turn them off. Alas, that doesn’t really work for me. That method installs a cookie, which is lost when you shut down and restart your browser. That's just snap.com being devious. They could install a cookie that would never time out, if they wanted to.
I’ve seen wildly conflicting reports about how to get rid of these things permanently. None of the solutions I read worked for me. Well, one solution is to switch to FireFox. It appears you can use its AdBlock feature to filter out the annoying little buggers forever. But I really don’t want to switch browsers. I’m sort of emotionally attached to Safari.
Being a technical-type guy, I went with the operating-system-level solution: modifying the hosts file. In case you don’t know, that’s a text file that resides on your local computer which helps guide DNS requests. In this case, it can be used to force lookups for snap.com’s evil domains to fail, so you won’t have to look at their crap. If you are on Windows, the hosts file is probably located at C:\Windows\SYSTEM32\hosts. on Macs and Linux/Unix computers, the file is at /etc/hosts.
These are the lines I added to the hosts file on my Mac:
If you don’t know what the hell I’m talking about, and you don’t have access to a local computer expert who does, you’re probably better off not trying this. But I can tell you that this worked for me. If snap.com changes the domains that they serve their ugly pop-ups from, then the list of hosts above would have to change, but the principal is basically sound.
Oh, and here’s another change you should make, which is a lot easier. Go to this page: http://www.livejournal.com/manage/settings/ and turn off the check box that says “Graphic Previews.” That will disable the nasty little buggers on your own personal LiveJournal. If everybody on LJ did that, the problem would be solved.