Who knows what kind of weird mathematical or scientific things have been discovered by hobbyists and posted on some obscure forum thread or abandoned blog that wasn't appreciated by anyone?
Like, if someone had a proof for the Goldbach Conjecture, and for whatever reason posted about it on the WatchUSeek forums (just as a throwaway example), it could just lay dormant for who knows how long? The audience on WatchUSeek might not realize the significance of a such a discovery, and maybe not even the poster, so it doesn't get any recognition and just never gets picked up.
I mean, going with the example in the original post, I don't know much about Superpermutations (only a little after this post went viral), so if I had seen this 4chan post in the wild, I would just assume it's some guy doing a bit of math that I wasn't familiar with. I wouldn't be able to spot that this was actually a contribution to anything.
On the other hand, it is nice and convenient if everything is indexed.
I dunno. Conflicted.
Still, I do wonder what cool (and real) stuff on the internet that people don't really know about is actually significant.