Safari Books is a pay-site that allows you to "check out" technical books up to a certain limit.

Every one in our group has an account, and we love it.

Unfortunately, the site, which O'Reilly runs, suffered from horrible usability issues.

Basically, they overdosed on Ajax, Ajaxifingy everything from search to flipping pages. Interestingly, the site used classical techniques for things that could have benefited from Ajax such as sign in and adding books to your self.

The new interfaced made searching and browsing for books a lot easier, but reading an individual book is still a chore and referring back to a specific spot in a book still requires an advanced degree.

And how about a social aspect to the site? I'd like to know what others are reading and see a break down of categories.

Still, it's a great site, and I'll continue to use it.