I know some ppl don't like suggesting whether fictional characters are aspie.... But really, Doesn't anyone think that Sai definately has aspergers. In the manga novel 35 - 38, sakura even says "watch sai, he can't read emotions"
Also, he studies books about how to lie and do facial expressions!
He also says he feels no emotion, but is striving to make friends.
I dont know whether mr kishimoto knew this when he created this character, as it says in wiki that "Sai has been trained to not possess or desire any type of emotion" but can you always trust wiki? lol. 