Here is a somewhat unique game that is inspired by the 2600 but really isn't a 2600 game. It can be played online or as a downloadable file. Here is some of the story from the game's web page:
For a brief time in 1983, rumors circulated about an advanced Atari VCS cartridge slated for release called "Black Lodge".
It was to be packed with enhanced chips, producing sound and graphics that were unprecedented on the system to that point.
Though production got far enough that a prospectus advertisement in Atari catalogs was run in select markets, the project was abruptly discontinued.
The next year, Pitfall 2: The Lost Caverns was released by Activision utilizing similarly enhanced chips, though it was nowhere near the sophistication that "Black Lodge" had promised.
Many in the industry assumed the designer had defected from Atari and brought the technology with him...
...except that the game was fully completed and was ready for release in 1983 when it was suddenly abandoned.
Stranger still, it quite directly references Twin Peaks, a television show that wouldn't air for another seven years.
What could this game's story be?