It is a good site. It is a good place to troll. You can download lots of porn from it. All kinds of porn can be found on 4chan. Well, as long as it is porn legal (according to US) laws. So the lolicon and shotacons fags will be happy, since 4chan allows lolicon and shotacon (as those are legal according to US laws).If you don't live in the US and live in a country where lolicon is illegal, then fuck it. Hide behind a proxy to download and upload your lolicon porn. Actually chances are your stupid government wouldn't even raid you for lolicon, so do it from your real ip address, you pedo-sick fuck.
There are lots of good trolls on 4chan.Actually trolling on 4chan is like taking a piss in a sea of piss, since trolling doesn't really make you stand out of the crowd. In order to stand out of the crowd, you need to be a total moralfag and newfag who posts his/her own facebook account on the goddamn site.
4chan is the home of Anonymous. All members of Anonymous treat 4chan as their Facebook. 4chan is where everyone posts as Anonymous, and various members of Anonymous Anonymously Communicate with each other. If you use 4chan and post anonymously on the site, congratulations you are a member of Anonymous. Now go on the deep webs to learn how to hack and then you can start bringing down some big corporations.
The only problem with 4chan is that you have to be obsessive basement dweller in order to keep your threads alive. That's because each thread on /b/ will quickly fall to the last page (the 15th one) if you don't attend to it (post on it frequently) enough to keep it alive on the front page.