The space elevator is one of my favorite topics. To date, no other technology to provide cheap access to space seems as viable.

For more info, here are a few links:

http://www.spaceward.org

http://www.spaceelevatorblog.com/

Also, this video isn't really technical, but I found it motivational:

http://www.youtube.com/watch?v=jfKKy33rb0U