Dish Network's streaming Internet television service, Sling TV, is now open to the public.

For $20 a month, Sling TV offers live access to ESPN, CNN, AMC, Adult Swim, Food Network and about a dozen other channels, without need for a cable or satellite subscription. As is typical with cable and satellite companies, Dish is upselling users by way of bundled channels. For an extra $5 each, on top of the standard $20 package, subscribers can add on channels such as the SEC Network and BeIn with "Sports Extra," or Disney...