As already mentioned -- the images are cheap to fix. Stick 'em up on S3 (with or without CDN), and they'll almost certainly be fine. General HTTP isn't someth

As already mentioned -- the images are cheap to fix. Stick 'em up on S3 (with or without CDN), and they'll almost certainly be fine. General HTTP isn't something we can really answer for you. If your PHP is memory intensive, there's a different remediation plan than if it's more CPU intensive. Regardless, you want to be leveraging a cache wherever you can. For the most part, unless you're excessively out of the norm on either memory or CPU, you'll likely be fine on a fairly small instance, so long as you abstract the DB away from there. Versus petervandijck's advice, I would recommend a number of smaller, load balanced EC2 instances instead of one big EC2 instance. It might add a little bit of complexity, but if you start off load balancing an $11 a month micro instance, it's easier to spin up additional instances as you need them, while keeping your base cost low. Alternately, you could of course spin up an $80 a month instance, and have less to worry about on the higher end, but it also costs more even if you aren't under load. As for the database, I'll leave that to my betters, but memcached is your friend.