Due to a number of deals with CBS and other companies kicking in, Netflix streaming has recently added the entire run of The Twilight Zone in HD, along with the first season of the Boris Karloff-hosted series Thriller. Netflix continues to increase its library and is quickly becoming a great place for horror fans to see classic horror films and shows, including those that may not have seen a DVD release.
If you haven't had a chance to see either anthology series, this is a great chance to catch up and well worth the price compared to the cost of buying them on Blu-ray or DVD. I've watched The Twilight Zone in every format available, and I'm still stunned by the quality of the HD transfer on the new releases.