nginx - A high performance free open source web server powering busiest sites on the Internet.
Barracuda Load Balancer ADC - Barracuda Load Balancer offers secure application delivery & load balancing.
Azure Traffic Manager - Microsoft Azure Traffic Manager allows you to control the distribution of user traffic for service endpoints in different datacenters.
Netflix Eureka - Eureka is a REST-based AWS service registry for resilient mid-tier load balancing and failover.
Haproxy - Reliable, High Performance TCP/HTTP Load Balancer
AWS Elastic Load Balancing - Amazon ELB automatically distributes incoming application traffic across multiple Amazon EC2 instances in the cloud.