Hello,

The Internet archive has made "The Console Living Room", where a lot of games can be played online:
https://archive.org/details/consolelivingroom

(the browser must have java enabled to play the games)

Bertus

 

I found an online "Colossal Cave" adventure game. http://www.amctv.com/shows/halt-and-catch-fire/colossal-cave-adventure
I had played this game on teletype terminals in the 70s. There are walkthroughs available if you are interested.

Spoiler

http://strategywiki.org/wiki/Colossal_Cave_Adventure/Walkthrough