[quote]"I know what the Librarian will say, Glassman. She will tell us where all things sacred are hidden in this galaxy. [b]Ships, weapons, bounties beyond our imagining.[/b]"[/quote] He knew about what the Janus Key would lead to before he even knew what the Key was, so this is what he's after - technology to uplift his people. It's probably going to tie back to what Guilty Spark said in CEA's Terminals about the "long plans" the Forerunners had in case of their tools being turned against them.