Fandoms
Most actors would be happy to land just one iconic role. With Indiana Jones, Harrison Ford nabbed the second such role of his career—the first, of course, being Han Solo. While the Indiana Jones franchise doesn't quite have a Star Wars-level following of fixated fans (but really, what else does?), it does retain legions of devoted Indy buffs.
The biggest Indiana Jones fan site on the web is TheRaider.net, which offers everything from news to features on each film to message boards, fan art, and tips for Indiana Jones cosplay. Fans who want to debate the merits of the Kingdom of the Crystal Skull or discuss what they want (or really, really don't want) to see in Indiana Jones 5 hash it out in the Indiana Jones subreddit.
And, of course, there's the Indiana Jones Wiki an exhaustively comprehensive online encyclopedia. Want to know what Indiana's sister's name was or what year Henry graduated college? This is the place.