Pound - HTTP Load Balancer and Reverse Proxy
Pound is a software HTTP Load Balancer and Reverse Proxy. Pound is a really simple server that forwards HTTP requests to the proper server or servers. You can set it up to have separate servers handle different types of content, or different parts of your web application (based on the url).
Pound can also provide sticky session based load balancing based on the value of a cookie, by a url param, by a HTTP authentication user, or by client IP address. So if you need to setup a load balanced CF application on a budget you can run this with two copies of CF Professional, or BlueDragon.