Sling TV customers could already add HBO to their streaming lineups, and now the service for cord cutters is adding another premium network. Cinemax is now available on Sling TV, bringing its library of movies and original series to the service for $10 a month. As part of that fee, you'll be privy to both live and on-demand content, the latter being the same stuff you'd find on Max Go. And there's all that After Dark entertainment, too. The main subscription costs $20 per month on its own, so if you want both HBO and Cinemax, you're looking at a $45 monthly fee.