Sure, but you're paying a price in terms of complexity: Many simple sites with PostgreSQL/MySQL can handle being slashdotted without having a cache (unless you'

Sure, but you're paying a price in terms of complexity: Many simple sites with PostgreSQL/MySQL can handle being slashdotted without having a cache (unless you're using a heavy CMS such as WordPress/Drupal). If you use SQLite, you might be forced to use Varnish - and there goes the initial idea of simplicity that caused you to use SQLite in the first place. Having said that, once your site goes truly high-traffic, you'll obviously need some caching. All I'm saying is that PostgreSQL/MySQL can easily handle moderately high traffic if your website is not a heavy CMS.