BlackBoxTV Presents, on YouTube
facebook; IMDb; official website; TV Tropes; Wikipedia; YouTube

So, this is like a horror/thriller anthology YouTube channel that debuted in 2010. I'm not sure when I first heard of it, but anyway, it's something I'd like to check out sometime.

Chilling Adventures of Sabrina, on Netflix
IMDb; TV Tango; TV Tropes; Wikia; Wikipedia

This is based on a comic book series I haven't read. It was originally meant to be set in the same universe as the CW's "Riverdale," which I haven't seen because I don't get the CW. But since it was picked up by Netflix instead of the CW, it's unclear whether or not there will be any crossovers.

Marble Hornets, on YouTube
IMDb; Slender Man Wiki; TV Tropes; Wikia; Wikipedia; YouTube

I guess this has to do with Slender Man. That's all I know.