The content choices just became more interesting for Google’s hot-selling $35 thumb-drive-sized dongle that brings Web content to TV sets. HBO GO pretty much had to make itself available on Chromecast: Users already can watch Netflix and Hulu Plus. The change means that HBO subscribers who have WiFi and Chromecast can watch shows on demand on TV sets that aren’t connected to a cable or satellite box. “Google’s Chromecast is one of the newest, more exciting devices in the marketplace today, so we are very happy to bring this capability to our subscribers,” says HBO’s Chief Technology Officer Otto Berkes. Google hasn’t released sales figures for Chromecast, but it’s Amazon’s top selling electronics device and ranks No. 2 among televisions and video products, and streaming media players.