>run a porn site and a non porn site with the same code base

so like reddit then

Reddit doesn't even separate them into 2 different sites.

Though there are a lot of niche and non-mainstream, and very user submitted porn subreddits.

And Tumblr? ;)

It's pretty much just ripped from Paul Graham's essay "what I've learned from hackernews": http://paulgraham.com/hackernews.html

"Software liberty" has a ring to it.