I had occasion over the last couple of days to work with the Network Load Balancing functionality that’s built into Windows 2000 Advanced Server.  I’m impressed at how painless it is to configure and operate.  Apart from a few ambiguities in the online help, things work exactly as I expected.  I haven’t yet tested the performance of my load balanced web servers except to show that the system does indeed work, and has somewhat higher throughput than the single web server.  For a large volume production web site, I’d rather go with a hardware load balancer/director, but for testing software in a load balanced environment, Microsoft’s NLB implementation is ideal.