Google Books

In spite of the current controversy surrounding copyright issues, I think it's admirable that this and other sites are making texts more and more available. Here's what Google says about their initiative:

"In May 1961, JFK said that he was going to put a man on the moon. The idea was unthinkable at the time, but within the decade, the goal was achieved. Google Book Search is our man on the moon initiative. We see a world where all books are online and searchable. How exactly will this be done? How long exactly will it take? We aren't sure, but we're committed to making it happen."

When you get there, read their "about" page.