Sega Channel was basically a smaller scale version of Netflix, but with genesis games. It was essentially a coax cable modem (at a time when even dialup was exceptionally rare) that you plugged into your genesis and when you turned it on, you would have a simple interface with a list of a dozen themes, and when you selected a theme it would be a list of a dozen games (those amounts may be off, this was over 20 years ago so I dont remember exactly). The genres and games would rotate monthly, and you COULD save games if you didnt download a new one. (Although this was something most people didnt know about). There were even game demos of stuff that hadnt came out yet.
In all honesty I still to this day dont understand how it didnt make a bigger impact.. it was truly a glimpse into the future and many people (even hardcore gamers) never heard of it.