He died quite young, didn't he? I know he is highly praised in Newmans "World of Mathematics"
Another who could have done much more was Dirac. I think I've made it up to about page 24 of his "The Principles of Quantum Mechanics"
But at least he talks about Bra vectors.
Who said nerds don't have a life?
;-)
Hey, he's in good company: Robinson (non-standard analysis), Bertrand Russell, Alfred North Whitehead, Alonzo Church, and Peano are all missing. But more to the point, while Ramanujan was brilliant and self-taught, his contributions didn't exactly "revolutionize" mathematics, due in part to his habit of asserting theorems without proof, and also by virtue of the fact that he died in his early 30's.