Eh, I run a one man shop, deliver on the order of 100k emails a day, and do most of what you describe on dedicated boxes (redis, queued jobs, mail server), and

Eh, I run a one man shop, deliver on the order of 100k emails a day, and do most of what you describe on dedicated boxes (redis, queued jobs, mail server), and it doesn't take that much time to administer. My 4 servers have a combined 36 3 ghz xeon processor cores, 12 TB of bandwidth, ~80 GB of RAM, and 8 SSD drives totaling 800 GB of flash. They serve about 11 million requests per day from 100k unique users at an average of 30-40 ms per request. They do this for less than $3k/month, and I've got about 4x headroom from midday steady state. It's not as redundant as Amazon's setup, but I've also had less downtime than EC2 in the last two years. IO is consistent, and almost always below 10ms. Setup and teardown is a pain, but I almost never have to do it. I've been able to put off hiring because it's not really that hard due to how powerful servers are these days. I'll admit to using S3 for picture hosting, but that's the only one :-)