Here’s a great resource for load balancing AJAX applications. Unlike most load balancing strategies.  This one outsources some of the responsibility for balancing to an AJAX client to reduce costs and increase availability.

 http://www.digital-web.com/articles/client_side_load_balancing/

This has been out there for quite a while now, but I thought it should be included in the bestiary out of completeness.

http://clientside.cnet.com