Why do people host static websites on S3 at all? It really isn't designed for that: it is an object store. Yes: it has a URL structure accessible in a way that makes it look like static hosting, and Amazon caved pretty early to people wanting to use it that way by adding features to make it more reasonable, but it doesn't fix the underlying problem.

Specifically, it is both allowed to--and often does--return 50x errors to requests. The documentation for the S3 API states you should immediately retry; that's fine for an API where I can code that logic into my client library, but is simply an unacceptable solution on the web. Maybe there are one or two exceptions to this, but I have simply never seen a web browser retry these requests: the result is you just get broken images, broken stylesheets, or even entire broken pages. Back when Twitter used to serve user avatar pictures directly from S3 the issue was downright endemic (as you'd often load a page with 30 small images to request from S3, so every few pages you'd come across a dud).

Sure, it only happens to some small percentage of requests, but for a popular website that can be a lot of people (and even for an unpopular one, every user counts), and it is orders of magnitude higher of a random error rate than I've experience with my own hosting on EC2; it is also irritating because it is random: when my own hosting fails, it fails in its entirely: I don't have some tiny fraction of requests for users all over the world failing.

Regardless, I actually have an administrative need to stop hosting a specific x.com to www.x.com redirect on some non-AWS hosting I have (the DNS is hosted by Route53, etc., but I was left with a dinky HTTP server in Kentucky somewhere handling the 301), and I figured "well, if it doesn't have to actually request through to an underlying storage system, maybe I won't run into problems; I mean, how hard is it to take a URL and just immediately return a 301?", but after just a few minutes of playing with it I managed to get a test request that was supposed to return a 301 returning a 500 error instead. :(

    HTTP/1.1 500 Internal Server Error
    x-amz-request-id: 1A631406498520D6
    x-amz-id-2: hXQ1YXyu0gxaiGITKvcB+P8+tgPsP3UITX/Or4emyjZtaL16ULAyHFx2ROT4QPXY
    Content-Type: text/html; charset=utf-8
    Content-Length: 354
    Date: Fri, 28 Dec 2012 07:19:24 GMT
    Connection: close
    Server: AmazonS3

This wasn't just a single-time problem either: I've setup a loop requesting random files (based on the timestamp of the test run and a sequence number from the test) off this pure-redirect bucket that I've left running for a few minutes, and some of the S3 nodes I'm talking to (72.21.194.13 being a great example) are just downright unreliable, often returning 500 errors in small clumps (that one node is giving me a 2% failure rate!!). S3 is simply not an appropriate mechanism for site hosting, and it is a shame that Amazon is encouraging people to misuse it in this fashion.

(edit: Great, and now someone downvoted me: would you like more evidence that this is a problem?)

I teach search and rescue people how to travel on skis or snowshoes and live in winter mountains. If you are prepared, you can stay out in sub-zero for days and days very comfortably.

A key skill is constant regulation of your body temperature. You never want to become too hot/sweaty or too cold. If too cold - get into shelter, drink something hot, eat carbs, add clothes, move faster. If too hot - remove clothes, or move slower. Fix temperature problems immediately - never tough it out.

Common mistakes: people get distracted by gadgets, or they get impatient and start to wander. Then they lose awareness of their body temperature, and become hypothermic. Once you get hypothermic, things fall apart fast.

If you do winter travel in remote areas, carry warm clothes, water and food. Then if you get stuck, be patient and steady. Follow this advice, and the odds of freezing to death go way down! :-)