Here's my setup:
Comcast Gigabit (1-Gbps down/35-Mbps up)
OTA antenna connected to Tablo allows me to stream OTA to any TV in the house. Tablo connects via WiFi, HDHomeRun over Ethernet. Just keep that in mind. 1-TB USB drive connected to Tablo for DVR.
Roku attached to all TVs in the house.
Plex Media Server running on a Western Digital NAS. I use it mainly for streaming music but I also ripped my entire DVD collection of movies and TV shows for streaming.
Hulu Live TV for cable channels
NetFlix. Although I would cancel it if it weren't for the wife and kids.
There's a ton of channels and a ton of content available for streaming on Roku. Some of my favorite free channels are YouTube, PlutoTV and CBS Sports HQ.