Ok, that doesn't include EBS and bandwidth. So let's throw in 1TB of outbound data (less than the 2TB that Rackspace includes, but still more than I'd ever use in a month) and a 150GB EBS volume with 1000 provision IOPS. Let's also use the 1 year heavy utilization price while we're at it. Now I'm looking $342/month with $1800 upfront, which amortizes to $492/month.
With AWS I also don't need to stick with paying 24x7 for infrastructure. I don't need to keep my CI infrastructure running on nights and weekends for example, and with AWS I have the flexibility to turn that into cost savings.
So I don't see the order of magnitude price difference. So maybe I shouldn't be looking at Rackspace? Hetzner keeps coming up on here, but I don't need a server in Europe. Maybe OVH? Hmm, the comments on Hacker News don't exactly inspire confidence in OVH for something more than a personal server to screw around with. I need to run infrastructure for my business. Do I start hunting for bargain hosting providers on WebHostingTalk?
Ok, back to AWS it is for me.
EDIT: Thanks for the suggestions to look at Softlayer. A server with 1 CPU and 8GB of RAM starts at $399, which is better than Rackspace, but not exactly orders of magnitude cheaper than the c1.xlarge I mentioned above.