We have been looking at Amazon EC2, and we like it. A lot.
The economics are simple and compelling for us. A single rack with 20 amps of power at our datacenter costs us about $1,000/month. With Amazon, for $1,000, I can get a nice database server class machine (about $300/month), a Pound load balancer machine ($75/month) and about 6 or 7 web server class machines ($75/month each). That’s about how much hardware a single rack at our datacenter can take before we start running out of power.
Our architecture allows for a hybrid configuration with some servers in the cloud and others (e.g., our mail servers and our database machines) in our datacenter. We are planning to try Amazon EC2 out for a few months by moving our QA test cluster out of our datacenter and up into the cloud.
Stay tuned. I will post an update in a few months.