I'm curious to know how Google stores the matrix that's used in the PageRank algorithm; and am looking for a data-structure for storing a very-large (not fitting in memory of any one computer) sparse matrix, and efficiently (not sure what that means yet) performing operations on it.
If there's a white-paper available please post a link or a title (I've done some research, and couldn't find one), and if not, it would be great if you could post links or just names of papers or books that would help get me started.
In my initial research I found the sparse row-wise format , and I started reading Sparse Matrix Technology ; so please let me if I'm on the right track here.
-  Chang, 1969 Curtis and Reid, 1971 Gustavson, 1972
-  Pissanetzky, 1984