Amazon Web Services's Elastic Compute Cloud (EC2) offers Elastic Load Balancing (ELB), a basic virtual load balancing appliance for applications running in EC2.
Testing and debugging ELBs can be a pain, especially because there are so many things to test.
This project is a collection of tools to help you test and debug your ELBs.
Check out the discussion group at http://groups.google.com/group/ec2-elb-tests .
The original articles presenting these tools are on Shlomo Swidler's Cloud Developer Tips blog: http://shlomoswidler.com/