Akinator, genie of the internet, is an online game based on twenty questions. In the game Akinator asks you a series of yes or no questions in order to try and guess the character you're thinking of. He usually makes a guess after the first twentyish questions. If he fails the first guess you can choose to keep going and he'll issue more questions or you can end the game and tell him who you were thinking of.
Akinator is surprisingly good (he got Tannis and @). This really ought not to be a surprise considering the game's database built from every play through. It's yet another example of the power of the internet hive mind. Link here.
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