Gotham Knights: 2043 was an online roleplaying game, run with two sets of teams - Alpha and Epsilon, though the latter was a secret team, led to believe they had connections to the official team.

The game ran for one RL year until, for a variety of reasons, the game was shut down by the gamemaster.

Gotham Knights: 2044 will be a tabletop game run at some point in the future. Maybe.  This is the only way a GK story will be told to it's conclusion, it seems. 

Gotham Knights: 1943 will be an online roleplaying game, run with one team - a group of agents secretly sent on a Top Secret mission, deep in Enemy Territory, to stop some terrible nefariousness from happening. Because Nazis were all about the nefarious, yo. This too, was shut down by the game master in Jan 2009.