To honor the memory of the late C. Martin Crocker (the voice of Zorak and Moltar, plus an animator for William's Street), Adult Swim has made most of Space Ghost Coast to Coast free to watch on their site
Why only "most" and not "all"? Best guess is they might still want people to buy the DVDs, since as of now the DVDs and iTunes are the only ways to watch the show in it's entirety (…well without resorting to "dubiously legal" means). But anyway yeah, if you're in the mood for this pre-Adult Swim William's Street classic then go have yourself a marathon!